20517964 has 24 divisors (see below), whose sum is σ = 37668960. Its totient is φ = 9765504.

The previous prime is 20517961. The next prime is 20517983. The reversal of 20517964 is 46971502.

It is a hoax number, since the sum of its digits (34) coincides with the sum of the digits of its distinct prime factors.

It is not an unprimeable number, because it can be changed into a prime (20517961) 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, 7257 + ... + 9679.

It is an arithmetic number, because the mean of its divisors is an integer number (1569540).

Almost surely, 2^20517964 is an apocalyptic number.

It is an amenable number.

20517964 is a deficient number, since it is larger than the sum of its proper divisors (17150996).

20517964 is a wasteful number, since it uses less digits than its factorization.

20517964 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2529 (or 2527 counting only the distinct ones).

The product of its (nonzero) digits is 15120, while the sum is 34.

The square root of 20517964 is about 4529.6759265978. The cubic root of 20517964 is about 273.7651031748.

The spelling of 20517964 in words is "twenty million, five hundred seventeen thousand, nine hundred sixty-four".