21495685 has 32 divisors (see below), whose sum is σ = 28449792. Its totient is φ = 15544320.

The previous prime is 21495673. The next prime is 21495703. The reversal of 21495685 is 58659412.

It is a de Polignac number, because none of the positive numbers 2^k-21495685 is a prime.

It is a Duffinian number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 221557 + ... + 221653.

It is an arithmetic number, because the mean of its divisors is an integer number (889056).

Almost surely, 2^21495685 is an apocalyptic number.

It is an amenable number.

21495685 is a deficient number, since it is larger than the sum of its proper divisors (6954107).

21495685 is a wasteful number, since it uses less digits than its factorization.

21495685 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 213.

The product of its digits is 86400, while the sum is 40.

The square root of 21495685 is about 4636.3439259831. The cubic root of 21495685 is about 278.0462847560.

The spelling of 21495685 in words is "twenty-one million, four hundred ninety-five thousand, six hundred eighty-five".