21999692 has 24 divisors (see below), whose sum is σ = 45231312. Its totient is φ = 9230400.

The previous prime is 21999689. The next prime is 21999721. The reversal of 21999692 is 29699912.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 18659 + ... + 19802.

It is an arithmetic number, because the mean of its divisors is an integer number (1884638).

Almost surely, 2^21999692 is an apocalyptic number.

21999692 is a gapful number since it is divisible by the number (22) formed by its first and last digit.

It is an amenable number.

21999692 is an abundant number, since it is smaller than the sum of its proper divisors (23231620).

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

21999692 is a wasteful number, since it uses less digits than its factorization.

21999692 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 38489 (or 38487 counting only the distinct ones).

The product of its digits is 157464, while the sum is 47.

The square root of 21999692 is about 4690.3829267982. The cubic root of 21999692 is about 280.2026254411.

The spelling of 21999692 in words is "twenty-one million, nine hundred ninety-nine thousand, six hundred ninety-two".