20517187018 has 32 divisors (see below), whose sum is σ = 33519225600. Its totient is φ = 9381633024.

The previous prime is 20517186953. The next prime is 20517187021. The reversal of 20517187018 is 81078171502.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 175938 + ... + 268306.

It is an arithmetic number, because the mean of its divisors is an integer number (1047475800).

Almost surely, 2^20517187018 is an apocalyptic number.

20517187018 is a deficient number, since it is larger than the sum of its proper divisors (13002038582).

20517187018 is a wasteful number, since it uses less digits than its factorization.

20517187018 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 92574.

The product of its (nonzero) digits is 31360, while the sum is 40.

The spelling of 20517187018 in words is "twenty billion, five hundred seventeen million, one hundred eighty-seven thousand, eighteen".