20399797377515 has 16 divisors (see below), whose sum is σ = 26204913676800. Its totient is φ = 15198849924192.

The previous prime is 20399797377503. The next prime is 20399797377563. The reversal of 20399797377515 is 51577379799302.

It is a cyclic number.

It is not a de Polignac number, because 20399797377515 - 2⁴ = 20399797377499 is a prime.

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, 1819780067 + ... + 1819791276.

It is an arithmetic number, because the mean of its divisors is an integer number (1637807104800).

Almost surely, 2^{20399797377515} is an apocalyptic number.

20399797377515 is a deficient number, since it is larger than the sum of its proper divisors (5805116299285).

20399797377515 is a wasteful number, since it uses less digits than its factorization.

20399797377515 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3639571426.

The product of its (nonzero) digits is 787648050, while the sum is 74.

The spelling of 20399797377515 in words is "twenty trillion, three hundred ninety-nine billion, seven hundred ninety-seven million, three hundred seventy-seven thousand, five hundred fifteen".