137816891 has 2 divisors, whose sum is σ = 137816892. Its totient is φ = 137816890.

The previous prime is 137816881. The next prime is 137816953. The reversal of 137816891 is 198618731.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 137816891 - 2⁶ = 137816827 is a prime.

It is a Sophie Germain prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (137816881) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 68908445 + 68908446.

It is an arithmetic number, because the mean of its divisors is an integer number (68908446).

Almost surely, 2^137816891 is an apocalyptic number.

137816891 is a deficient number, since it is larger than the sum of its proper divisors (1).

137816891 is an equidigital number, since it uses as much as digits as its factorization.

137816891 is an evil number, because the sum of its binary digits is even.

The product of its digits is 72576, while the sum is 44.

The square root of 137816891 is about 11739.5439008507. The cubic root of 137816891 is about 516.5362629388.

It can be divided in two parts, 13781 and 6891, that multiplied together give a triangular number (94964871 = T₁₃₇₈₁).

The spelling of 137816891 in words is "one hundred thirty-seven million, eight hundred sixteen thousand, eight hundred ninety-one".