155139931551 has 32 divisors (see below), whose sum is σ = 239233038336. Its totient is φ = 88531920000.

The previous prime is 155139931547. The next prime is 155139931561.

155139931551 is nontrivially palindromic in base 10.

It is not a de Polignac number, because 155139931551 - 2² = 155139931547 is a prime.

It is a Smith number, since the sum of its digits (48) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a self number, because there is not a number n which added to its sum of digits gives 155139931551.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (155139931561) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 2011500 + ... + 2087201.

It is an arithmetic number, because the mean of its divisors is an integer number (7476032448).

Almost surely, 2^155139931551 is an apocalyptic number.

155139931551 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

155139931551 is a deficient number, since it is larger than the sum of its proper divisors (84093106785).

155139931551 is a wasteful number, since it uses less digits than its factorization.

155139931551 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4098783.

The product of its digits is 455625, while the sum is 48.

The spelling of 155139931551 in words is "one hundred fifty-five billion, one hundred thirty-nine million, nine hundred thirty-one thousand, five hundred fifty-one".