21107625 has 128 divisors (see below), whose sum is σ = 47443968. Its totient is φ = 8064000.

The previous prime is 21107587. The next prime is 21107633. The reversal of 21107625 is 52670112.

It is not a de Polignac number, because 21107625 - 2⁶ = 21107561 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 21107595 and 21107604.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 127 ways as a sum of consecutive naturals, for example, 490854 + ... + 490896.

It is an arithmetic number, because the mean of its divisors is an integer number (370656).

Almost surely, 2^21107625 is an apocalyptic number.

21107625 is a gapful number since it is divisible by the number (25) formed by its first and last digit.

It is an amenable number.

21107625 is an abundant number, since it is smaller than the sum of its proper divisors (26336343).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

21107625 is a wasteful number, since it uses less digits than its factorization.

21107625 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 96 (or 86 counting only the distinct ones).

The product of its (nonzero) digits is 840, while the sum is 24.

The square root of 21107625 is about 4594.3035380784. The cubic root of 21107625 is about 276.3629309711.

Adding to 21107625 its reverse (52670112), we get a palindrome (73777737).

The spelling of 21107625 in words is "twenty-one million, one hundred seven thousand, six hundred twenty-five".