21310992 has 40 divisors (see below), whose sum is σ = 61171680. Its totient is φ = 7103520.

The previous prime is 21310957. The next prime is 21310999. The reversal of 21310992 is 29901312.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is not an unprimeable number, because it can be changed into a prime (21310999) 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, 24234 + ... + 25097.

It is an arithmetic number, because the mean of its divisors is an integer number (1529292).

Almost surely, 2^21310992 is an apocalyptic number.

It is an amenable number.

21310992 is an abundant number, since it is smaller than the sum of its proper divisors (39860688).

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

21310992 is a wasteful number, since it uses less digits than its factorization.

21310992 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 49348 (or 49336 counting only the distinct ones).

The product of its (nonzero) digits is 972, while the sum is 27.

The square root of 21310992 is about 4616.3829997088. The cubic root of 21310992 is about 277.2476595777.

The spelling of 21310992 in words is "twenty-one million, three hundred ten thousand, nine hundred ninety-two".