1997515956128 has 48 divisors (see below), whose sum is σ = 4902993716544. Its totient is φ = 778252968960.

The previous prime is 1997515956109. The next prime is 1997515956167. The reversal of 1997515956128 is 8216595157991.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 405337625 + ... + 405342552.

It is an arithmetic number, because the mean of its divisors is an integer number (102145702428).

Almost surely, 2^{1997515956128} is an apocalyptic number.

It is an amenable number.

1997515956128 is an abundant number, since it is smaller than the sum of its proper divisors (2905477760416).

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

1997515956128 is a wasteful number, since it uses less digits than its factorization.

1997515956128 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 810680205 (or 810680197 counting only the distinct ones).

The product of its digits is 61236000, while the sum is 68.

The spelling of 1997515956128 in words is "one trillion, nine hundred ninety-seven billion, five hundred fifteen million, nine hundred fifty-six thousand, one hundred twenty-eight".