421686225 has 45 divisors (see below), whose sum is σ = 776267063. Its totient is φ = 218820960.

The previous prime is 421686197. The next prime is 421686227. The reversal of 421686225 is 522686124.

It is a happy number.

The square root of 421686225 is 20535.

It is a perfect power (a square), and thus also a powerful number.

421686225 is a `hidden beast` number, since 4 + 21 + 6 + 8 + 622 + 5 = 666.

It can be written as a sum of positive squares in 7 ways, for example, as 123201 + 421563024 = 351^2 + 20532^2 .

It is a tau number, because it is divible by the number of its divisors (45).

It is not a de Polignac number, because 421686225 - 2⁵ = 421686193 is a prime.

It is a Duffinian number.

Its product of digits (46080) is a multiple of the sum of its prime divisors (45).

It is a Curzon number.

It is a self number, because there is not a number n which added to its sum of digits gives 421686225.

It is not an unprimeable number, because it can be changed into a prime (421686227) by changing a digit.

It is a polite number, since it can be written in 44 ways as a sum of consecutive naturals, for example, 11396907 + ... + 11396943.

Almost surely, 2^421686225 is an apocalyptic number.

421686225 is a gapful number since it is divisible by the number (45) formed by its first and last digit.

421686225 is the 20535-th square number.

421686225 is the 10268-th centered octagonal number.

It is an amenable number.

421686225 is a deficient number, since it is larger than the sum of its proper divisors (354580838).

421686225 is an frugal number, since it uses more digits than its factorization.

421686225 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 164 (or 45 counting only the distinct ones).

The product of its digits is 46080, while the sum is 36.

The cubic root of 421686225 is about 749.8881166436. Note that the first 3 decimals are identical.

Multiplying 421686225 by its sum of digits (36), we get a square (15180704100 = 123210²).

The spelling of 421686225 in words is "four hundred twenty-one million, six hundred eighty-six thousand, two hundred twenty-five".