137255021 has 2 divisors, whose sum is σ = 137255022. Its totient is φ = 137255020.

The previous prime is 137254987. The next prime is 137255023. The reversal of 137255021 is 120552731.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 106894921 + 30360100 = 10339^2 + 5510^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-137255021 is a prime.

Together with 137255023, it forms a pair of twin primes.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (137255023) 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 as a sum of consecutive naturals, namely, 68627510 + 68627511.

It is an arithmetic number, because the mean of its divisors is an integer number (68627511).

Almost surely, 2^137255021 is an apocalyptic number.

It is an amenable number.

137255021 is a deficient number, since it is larger than the sum of its proper divisors (1).

137255021 is an equidigital number, since it uses as much as digits as its factorization.

137255021 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 2100, while the sum is 26.

The square root of 137255021 is about 11715.5888029582. The cubic root of 137255021 is about 515.8333458665.

The spelling of 137255021 in words is "one hundred thirty-seven million, two hundred fifty-five thousand, twenty-one".