157731881 has 2 divisors, whose sum is σ = 157731882. Its totient is φ = 157731880.

The previous prime is 157731823. The next prime is 157731911. The reversal of 157731881 is 188137751.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 133633600 + 24098281 = 11560^2 + 4909^2 .

It is a cyclic number.

It is not a de Polignac number, because 157731881 - 2¹⁰ = 157730857 is a prime.

It is a super-2 number, since 2×157731881² = 49758692567596322, which contains 22 as substring.

It is a Sophie Germain prime.

It is a Chen prime.

It is a Curzon number.

It is not a weakly prime, because it can be changed into another prime (157731281) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 78865940 + 78865941.

It is an arithmetic number, because the mean of its divisors is an integer number (78865941).

Almost surely, 2^157731881 is an apocalyptic number.

It is an amenable number.

157731881 is a deficient number, since it is larger than the sum of its proper divisors (1).

157731881 is an equidigital number, since it uses as much as digits as its factorization.

157731881 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 47040, while the sum is 41.

The square root of 157731881 is about 12559.1353603662. The cubic root of 157731881 is about 540.3060462222.

The spelling of 157731881 in words is "one hundred fifty-seven million, seven hundred thirty-one thousand, eight hundred eighty-one".