138909001657961 has 2 divisors, whose sum is σ = 138909001657962. Its totient is φ = 138909001657960.

The previous prime is 138909001657957. The next prime is 138909001658017. The reversal of 138909001657961 is 169756100909831.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 124086655657561 + 14822346000400 = 11139419^2 + 3849980^2 .

It is a cyclic number.

It is not a de Polignac number, because 138909001657961 - 2² = 138909001657957 is a prime.

It is a super-3 number, since 3×138909001657961³ (a number of 43 digits) contains 333 as substring. Note that it is a super-d number also for d = 2.

It is not a weakly prime, because it can be changed into another prime (138909001687961) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 69454500828980 + 69454500828981.

It is an arithmetic number, because the mean of its divisors is an integer number (69454500828981).

Almost surely, 2^{138909001657961} is an apocalyptic number.

It is an amenable number.

138909001657961 is a deficient number, since it is larger than the sum of its proper divisors (1).

138909001657961 is an equidigital number, since it uses as much as digits as its factorization.

138909001657961 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 22044960, while the sum is 65.

The spelling of 138909001657961 in words is "one hundred thirty-eight trillion, nine hundred nine billion, one million, six hundred fifty-seven thousand, nine hundred sixty-one".