111257661324891 has 16 divisors (see below), whose sum is σ = 148872463170048. Its totient is φ = 73907320401600.

The previous prime is 111257661324857. The next prime is 111257661324913. The reversal of 111257661324891 is 198423166752111.

It is a happy number.

It is not a de Polignac number, because 111257661324891 - 2¹⁵ = 111257661292123 is a prime.

It is not an unprimeable number, because it can be changed into a prime (111257661324851) 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 15 ways as a sum of consecutive naturals, for example, 158733690 + ... + 159433056.

It is an arithmetic number, because the mean of its divisors is an integer number (9304528948128).

Almost surely, 2^{111257661324891} is an apocalyptic number.

111257661324891 is a deficient number, since it is larger than the sum of its proper divisors (37614801845157).

111257661324891 is a wasteful number, since it uses less digits than its factorization.

111257661324891 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 888362.

The product of its digits is 4354560, while the sum is 57.

The spelling of 111257661324891 in words is "one hundred eleven trillion, two hundred fifty-seven billion, six hundred sixty-one million, three hundred twenty-four thousand, eight hundred ninety-one".