137321521 has 2 divisors, whose sum is σ = 137321522. Its totient is φ = 137321520.

The previous prime is 137321501. The next prime is 137321549. The reversal of 137321521 is 125123731.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 77088400 + 60233121 = 8780^2 + 7761^2 .

It is an emirp because it is prime and its reverse (125123731) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 137321521 - 2¹¹ = 137319473 is a prime.

It is not a weakly prime, because it can be changed into another prime (137321501) 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, 68660760 + 68660761.

It is an arithmetic number, because the mean of its divisors is an integer number (68660761).

Almost surely, 2^137321521 is an apocalyptic number.

It is an amenable number.

137321521 is a deficient number, since it is larger than the sum of its proper divisors (1).

137321521 is an equidigital number, since it uses as much as digits as its factorization.

137321521 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 1260, while the sum is 25.

The square root of 137321521 is about 11718.4265582031. The cubic root of 137321521 is about 515.9166394292.

The spelling of 137321521 in words is "one hundred thirty-seven million, three hundred twenty-one thousand, five hundred twenty-one".