21260625 has 80 divisors (see below), whose sum is σ = 40487040. Its totient is φ = 9856000.

The previous prime is 21260623. The next prime is 21260647. The reversal of 21260625 is 52606212.

It is not a de Polignac number, because 21260625 - 2¹ = 21260623 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 21260595 and 21260604.

It is not an unprimeable number, because it can be changed into a prime (21260621) by changing a digit.

It is a polite number, since it can be written in 79 ways as a sum of consecutive naturals, for example, 733111 + ... + 733139.

It is an arithmetic number, because the mean of its divisors is an integer number (506088).

Almost surely, 2^21260625 is an apocalyptic number.

21260625 is a gapful number since it is divisible by the number (25) formed by its first and last digit.

21260625 is the 2465-th nonagonal number.

It is an amenable number.

21260625 is a deficient number, since it is larger than the sum of its proper divisors (19226415).

21260625 is a wasteful number, since it uses less digits than its factorization.

21260625 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 92 (or 77 counting only the distinct ones).

The product of its (nonzero) digits is 1440, while the sum is 24.

The square root of 21260625 is about 4610.9245276842. The cubic root of 21260625 is about 277.0290689647.

Adding to 21260625 its reverse (52606212), we get a palindrome (73866837).

The spelling of 21260625 in words is "twenty-one million, two hundred sixty thousand, six hundred twenty-five".