21690704 has 40 divisors (see below), whose sum is σ = 50562240. Its totient is φ = 8805888.

The previous prime is 21690703. The next prime is 21690707. The reversal of 21690704 is 40709612.

It is a super-3 number, since 3×21690704³ (a number of 23 digits) contains 333 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21690703) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 2969 + ... + 7224.

It is an arithmetic number, because the mean of its divisors is an integer number (1264056).

Almost surely, 2^21690704 is an apocalyptic number.

It is an amenable number.

21690704 is an abundant number, since it is smaller than the sum of its proper divisors (28871536).

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

21690704 is a wasteful number, since it uses less digits than its factorization.

21690704 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10227 (or 10221 counting only the distinct ones).

The product of its (nonzero) digits is 3024, while the sum is 29.

The square root of 21690704 is about 4657.3279893089. The cubic root of 21690704 is about 278.8846103256.

The spelling of 21690704 in words is "twenty-one million, six hundred ninety thousand, seven hundred four".