136731281391 has 20 divisors (see below), whose sum is σ = 205066688904. Its totient is φ = 90791010000.

The previous prime is 136731281377. The next prime is 136731281431. The reversal of 136731281391 is 193182137631.

136731281391 is a `hidden beast` number, since 1 + 367 + 3 + 1 + 281 + 3 + 9 + 1 = 666.

It is not a de Polignac number, because 136731281391 - 2⁹ = 136731280879 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (136731281891) by changing a digit.

It is a polite number, since it can be written in 19 ways as a sum of consecutive naturals, for example, 3342300 + ... + 3382961.

Almost surely, 2^136731281391 is an apocalyptic number.

136731281391 is a deficient number, since it is larger than the sum of its proper divisors (68335407513).

136731281391 is an equidigital number, since it uses as much as digits as its factorization.

136731281391 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6725524 (or 6725515 counting only the distinct ones).

The product of its digits is 163296, while the sum is 45.

The spelling of 136731281391 in words is "one hundred thirty-six billion, seven hundred thirty-one million, two hundred eighty-one thousand, three hundred ninety-one".