139935388031981 has 2 divisors, whose sum is σ = 139935388031982. Its totient is φ = 139935388031980.

The previous prime is 139935388031977. The next prime is 139935388032001. The reversal of 139935388031981 is 189130883539931.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 117959366028100 + 21976022003881 = 10860910^2 + 4687859^2 .

It is a cyclic number.

It is not a de Polignac number, because 139935388031981 - 2² = 139935388031977 is a prime.

It is a super-2 number, since 2×139935388031981² (a number of 29 digits) contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (139935388031941) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (29) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 69967694015990 + 69967694015991.

It is an arithmetic number, because the mean of its divisors is an integer number (69967694015991).

Almost surely, 2^{139935388031981} is an apocalyptic number.

It is an amenable number.

139935388031981 is a deficient number, since it is larger than the sum of its proper divisors (1).

139935388031981 is an equidigital number, since it uses as much as digits as its factorization.

139935388031981 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 151165440, while the sum is 71.

The spelling of 139935388031981 in words is "one hundred thirty-nine trillion, nine hundred thirty-five billion, three hundred eighty-eight million, thirty-one thousand, nine hundred eighty-one".