20517572 has 24 divisors (see below), whose sum is σ = 38741976. Its totient is φ = 9471488.

The previous prime is 20517557. The next prime is 20517577. The reversal of 20517572 is 27571502.

It can be written as a sum of positive squares in 4 ways, for example, as 3740356 + 16777216 = 1934^2 + 4096^2 .

It is not an unprimeable number, because it can be changed into a prime (20517577) 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, 758 + ... + 6450.

It is an arithmetic number, because the mean of its divisors is an integer number (1614249).

Almost surely, 2^20517572 is an apocalyptic number.

It is an amenable number.

20517572 is a deficient number, since it is larger than the sum of its proper divisors (18224404).

20517572 is a wasteful number, since it uses less digits than its factorization.

20517572 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5767 (or 5765 counting only the distinct ones).

The product of its (nonzero) digits is 4900, while the sum is 29.

The square root of 20517572 is about 4529.6326561875. The cubic root of 20517572 is about 273.7633597172.

The spelling of 20517572 in words is "twenty million, five hundred seventeen thousand, five hundred seventy-two".