20205972 has 18 divisors (see below), whose sum is σ = 51076298. Its totient is φ = 6735312.

The previous prime is 20205947. The next prime is 20206009. The reversal of 20205972 is 27950202.

It is a happy number.

It can be written as a sum of positive squares in only one way, i.e., 20034576 + 171396 = 4476^2 + 414^2 .

It is a tau number, because it is divible by the number of its divisors (18).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 280603 + ... + 280674.

Almost surely, 2^20205972 is an apocalyptic number.

It is an amenable number.

20205972 is an abundant number, since it is smaller than the sum of its proper divisors (30870326).

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

20205972 is a wasteful number, since it uses less digits than its factorization.

20205972 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 561287 (or 561282 counting only the distinct ones).

The product of its (nonzero) digits is 2520, while the sum is 27.

The square root of 20205972 is about 4495.1053380316. The cubic root of 20205972 is about 272.3704043868.

The spelling of 20205972 in words is "twenty million, two hundred five thousand, nine hundred seventy-two".