21960972 has 36 divisors (see below), whose sum is σ = 60560136. Its totient is φ = 6654720.

The previous prime is 21960947. The next prime is 21960977. The reversal of 21960972 is 27906912.

It is a tau number, because it is divible by the number of its divisors (36).

It is a Harshad number since it is a multiple of its sum of digits (36).

It is not an unprimeable number, because it can be changed into a prime (21960977) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 27333 + ... + 28124.

It is an arithmetic number, because the mean of its divisors is an integer number (1682226).

Almost surely, 2^21960972 is an apocalyptic number.

21960972 is a gapful number since it is divisible by the number (22) formed by its first and last digit.

It is an amenable number.

21960972 is an abundant number, since it is smaller than the sum of its proper divisors (38599164).

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

21960972 is a wasteful number, since it uses less digits than its factorization.

21960972 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 55478 (or 55473 counting only the distinct ones).

The product of its (nonzero) digits is 13608, while the sum is 36.

The square root of 21960972 is about 4686.2535142692. The cubic root of 21960972 is about 280.0381410628.

The spelling of 21960972 in words is "twenty-one million, nine hundred sixty thousand, nine hundred seventy-two".