137781857 has 2 divisors, whose sum is σ = 137781858. Its totient is φ = 137781856.

The previous prime is 137781851. The next prime is 137781911. The reversal of 137781857 is 758187731.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 130896481 + 6885376 = 11441^2 + 2624^2 .

It is a cyclic number.

It is not a de Polignac number, because 137781857 - 2⁴ = 137781841 is a prime.

It is not a weakly prime, because it can be changed into another prime (137781851) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 68890928 + 68890929.

It is an arithmetic number, because the mean of its divisors is an integer number (68890929).

Almost surely, 2^137781857 is an apocalyptic number.

It is an amenable number.

137781857 is a deficient number, since it is larger than the sum of its proper divisors (1).

137781857 is an equidigital number, since it uses as much as digits as its factorization.

137781857 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 329280, while the sum is 47.

The square root of 137781857 is about 11738.0516696767. The cubic root of 137781857 is about 516.4924902079.

The spelling of 137781857 in words is "one hundred thirty-seven million, seven hundred eighty-one thousand, eight hundred fifty-seven".