21936970 has 32 divisors (see below), whose sum is σ = 45614016. Its totient is φ = 7507200.

The previous prime is 21936961. The next prime is 21936973. The reversal of 21936970 is 7963912.

It is not an unprimeable number, because it can be changed into a prime (21936973) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 3996 + ... + 7735.

It is an arithmetic number, because the mean of its divisors is an integer number (1425438).

Almost surely, 2^21936970 is an apocalyptic number.

21936970 is an abundant number, since it is smaller than the sum of its proper divisors (23677046).

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

21936970 is a wasteful number, since it uses less digits than its factorization.

21936970 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 11766.

The product of its (nonzero) digits is 20412, while the sum is 37.

The square root of 21936970 is about 4683.6919198427. The cubic root of 21936970 is about 279.9360823489.

The spelling of 21936970 in words is "twenty-one million, nine hundred thirty-six thousand, nine hundred seventy".