21929312 has 24 divisors (see below), whose sum is σ = 44180136. Its totient is φ = 10708992.

The previous prime is 21929293. The next prime is 21929321. The reversal of 21929312 is 21392912.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 6593 + ... + 9344.

It is an arithmetic number, because the mean of its divisors is an integer number (1840839).

Almost surely, 2^21929312 is an apocalyptic number.

It is an amenable number.

21929312 is an abundant number, since it is smaller than the sum of its proper divisors (22250824).

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

21929312 is a wasteful number, since it uses less digits than its factorization.

21929312 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 15990 (or 15982 counting only the distinct ones).

The product of its digits is 1944, while the sum is 29.

The square root of 21929312 is about 4682.8743310065. The cubic root of 21929312 is about 279.9035041636.

The spelling of 21929312 in words is "twenty-one million, nine hundred twenty-nine thousand, three hundred twelve".