915157911990 has 32 divisors (see below), whose sum is σ = 2510147416320. Its totient is φ = 209178951264.

The previous prime is 915157911931. The next prime is 915157912007. The reversal of 915157911990 is 99119751519.

915157911990 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a self number, because there is not a number n which added to its sum of digits gives 915157911990.

It is a congruent number.

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, 2178947200 + ... + 2178947619.

It is an arithmetic number, because the mean of its divisors is an integer number (78442106760).

Almost surely, 2^915157911990 is an apocalyptic number.

915157911990 is an abundant number, since it is smaller than the sum of its proper divisors (1594989504330).

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

915157911990 is a wasteful number, since it uses less digits than its factorization.

915157911990 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4357894836.

The product of its (nonzero) digits is 1148175, while the sum is 57.

The spelling of 915157911990 in words is "nine hundred fifteen billion, one hundred fifty-seven million, nine hundred eleven thousand, nine hundred ninety".