421821125 has 36 divisors (see below), whose sum is σ = 582126636. Its totient is φ = 304942000.

The previous prime is 421821121. The next prime is 421821131. The reversal of 421821125 is 521128124.

It is a powerful number, because all its prime factors have an exponent greater than 1 and also an Achilles number because it is not a perfect power.

It can be written as a sum of positive squares in 2 ways, for example, as 13498276 + 408322849 = 3674^2 + 20207^2 .

It is not a de Polignac number, because 421821125 - 2² = 421821121 is a prime.

It is a super-2 number, since 2×421821125² = 355866122992531250, which contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 421821094 and 421821103.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (421821121) by changing a digit.

It is a polite number, since it can be written in 35 ways as a sum of consecutive naturals, for example, 2525792 + ... + 2525958.

Almost surely, 2^421821125 is an apocalyptic number.

It is an amenable number.

421821125 is a deficient number, since it is larger than the sum of its proper divisors (160305511).

421821125 is an equidigital number, since it uses as much as digits as its factorization.

421821125 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 371 (or 183 counting only the distinct ones).

The product of its digits is 1280, while the sum is 26.

The square root of 421821125 is about 20538.2843733356. The cubic root of 421821125 is about 749.9680727150.

Multiplying 421821125 by its product of digits (1280), we get a square (539931040000 = 734800²).

Adding to 421821125 its reverse (521128124), we get a palindrome (942949249).

The spelling of 421821125 in words is "four hundred twenty-one million, eight hundred twenty-one thousand, one hundred twenty-five".