21929704 has 16 divisors (see below), whose sum is σ = 41894820. Its totient is φ = 10757760.

The previous prime is 21929701. The next prime is 21929707. The reversal of 21929704 is 40792912.

It is a happy number.

It is an interprime number because it is at equal distance from previous prime (21929701) and next prime (21929707).

It can be written as a sum of positive squares in 2 ways, for example, as 21436900 + 492804 = 4630^2 + 702^2 .

It is a self number, because there is not a number n which added to its sum of digits gives 21929704.

It is not an unprimeable number, because it can be changed into a prime (21929701) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 25437 + ... + 26284.

Almost surely, 2^21929704 is an apocalyptic number.

It is an amenable number.

21929704 is a deficient number, since it is larger than the sum of its proper divisors (19965116).

21929704 is a wasteful number, since it uses less digits than its factorization.

21929704 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 51780 (or 51776 counting only the distinct ones).

The product of its (nonzero) digits is 9072, while the sum is 34.

The square root of 21929704 is about 4682.9161854554. The cubic root of 21929704 is about 279.9051719697.

The spelling of 21929704 in words is "twenty-one million, nine hundred twenty-nine thousand, seven hundred four".