8139781157 has 16 divisors (see below), whose sum is σ = 8357090112. Its totient is φ = 7925808000.

The previous prime is 8139781141. The next prime is 8139781163. The reversal of 8139781157 is 7511879318.

It is a cyclic number.

It is not a de Polignac number, because 8139781157 - 2⁴ = 8139781141 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (8139781757) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 2302163 + ... + 2305695.

It is an arithmetic number, because the mean of its divisors is an integer number (522318132).

Almost surely, 2^8139781157 is an apocalyptic number.

It is an amenable number.

8139781157 is a deficient number, since it is larger than the sum of its proper divisors (217308955).

8139781157 is a wasteful number, since it uses less digits than its factorization.

8139781157 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3988.

The product of its digits is 423360, while the sum is 50.

The square root of 8139781157 is about 90220.7357374124. The cubic root of 8139781157 is about 2011.5812377713.

The spelling of 8139781157 in words is "eight billion, one hundred thirty-nine million, seven hundred eighty-one thousand, one hundred fifty-seven".