21273625 has 8 divisors (see below), whose sum is σ = 26549640. Its totient is φ = 17018800.

The previous prime is 21273611. The next prime is 21273641. The reversal of 21273625 is 52637212.

It can be written as a sum of positive squares in 4 ways, for example, as 2368521 + 18905104 = 1539^2 + 4348^2 .

It is not a de Polignac number, because 21273625 - 2²¹ = 19176473 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 21273593 and 21273602.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 84970 + ... + 85219.

It is an arithmetic number, because the mean of its divisors is an integer number (3318705).

Almost surely, 2^21273625 is an apocalyptic number.

21273625 is a gapful number since it is divisible by the number (25) formed by its first and last digit.

It is an amenable number.

21273625 is a deficient number, since it is larger than the sum of its proper divisors (5276015).

21273625 is an equidigital number, since it uses as much as digits as its factorization.

21273625 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 170204 (or 170194 counting only the distinct ones).

The product of its digits is 5040, while the sum is 28.

The square root of 21273625 is about 4612.3340078533. The cubic root of 21273625 is about 277.0855214305.

It can be divided in two parts, 212 and 73625, that added together give a palindrome (73837).

The spelling of 21273625 in words is "twenty-one million, two hundred seventy-three thousand, six hundred twenty-five".