137856391 has 8 divisors (see below), whose sum is σ = 143614800. Its totient is φ = 132212160.

The previous prime is 137856379. The next prime is 137856403. The reversal of 137856391 is 193658731.

It is an interprime number because it is at equal distance from previous prime (137856379) and next prime (137856403).

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 137856391 - 2²³ = 129467783 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (137856331) 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 in 7 ways as a sum of consecutive naturals, for example, 26076 + ... + 30913.

It is an arithmetic number, because the mean of its divisors is an integer number (17951850).

Almost surely, 2^137856391 is an apocalyptic number.

137856391 is a deficient number, since it is larger than the sum of its proper divisors (5758409).

137856391 is an equidigital number, since it uses as much as digits as its factorization.

137856391 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 57089.

The product of its digits is 136080, while the sum is 43.

The square root of 137856391 is about 11741.2261284757. The cubic root of 137856391 is about 516.5856067536.

The spelling of 137856391 in words is "one hundred thirty-seven million, eight hundred fifty-six thousand, three hundred ninety-one".