21959770 has 16 divisors (see below), whose sum is σ = 45174528. Its totient is φ = 7529040.

The previous prime is 21959761. The next prime is 21959789. The reversal of 21959770 is 7795912.

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, 156786 + ... + 156925.

It is an arithmetic number, because the mean of its divisors is an integer number (2823408).

Almost surely, 2^21959770 is an apocalyptic number.

21959770 is an abundant number, since it is smaller than the sum of its proper divisors (23214758).

21959770 is a wasteful number, since it uses less digits than its factorization.

21959770 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 313725.

The product of its (nonzero) digits is 39690, while the sum is 40.

The square root of 21959770 is about 4686.1252650777. The cubic root of 21959770 is about 280.0330318173.

The spelling of 21959770 in words is "twenty-one million, nine hundred fifty-nine thousand, seven hundred seventy".