156981831 has 16 divisors (see below), whose sum is σ = 222117120. Its totient is φ = 98405120.

The previous prime is 156981829. The next prime is 156981841. The reversal of 156981831 is 138189651.

It is a cyclic number.

It is not a de Polignac number, because 156981831 - 2¹ = 156981829 is a prime.

It is a super-2 number, since 2×156981831² = 49286590528225122, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (156981841) 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, 15210 + ... + 23351.

It is an arithmetic number, because the mean of its divisors is an integer number (13882320).

Almost surely, 2^156981831 is an apocalyptic number.

156981831 is a deficient number, since it is larger than the sum of its proper divisors (65135289).

156981831 is a wasteful number, since it uses less digits than its factorization.

156981831 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 38646.

The product of its digits is 51840, while the sum is 42.

The square root of 156981831 is about 12529.2390431343. The cubic root of 156981831 is about 539.4482601883.

The spelling of 156981831 in words is "one hundred fifty-six million, nine hundred eighty-one thousand, eight hundred thirty-one".