156442871781 has 120 divisors (see below), whose sum is σ = 273266456320. Its totient is φ = 86149526400.

The previous prime is 156442871737. The next prime is 156442871797. The reversal of 156442871781 is 187178244651.

It is a happy number.

156442871781 is a `hidden beast` number, since 1 + 56 + 442 + 8 + 71 + 7 + 81 = 666.

It is not a de Polignac number, because 156442871781 - 2⁹ = 156442871269 is a prime.

It is a super-2 number, since 2×156442871781² (a number of 23 digits) contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (156442871681) by changing a digit.

It is a polite number, since it can be written in 119 ways as a sum of consecutive naturals, for example, 273980226 + ... + 273980796.

Almost surely, 2^156442871781 is an apocalyptic number.

It is an amenable number.

156442871781 is a deficient number, since it is larger than the sum of its proper divisors (116823584539).

156442871781 is an equidigital number, since it uses as much as digits as its factorization.

156442871781 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1045 (or 1021 counting only the distinct ones).

The product of its digits is 3010560, while the sum is 54.

The spelling of 156442871781 in words is "one hundred fifty-six billion, four hundred forty-two million, eight hundred seventy-one thousand, seven hundred eighty-one".