139805957 has 2 divisors, whose sum is σ = 139805958. Its totient is φ = 139805956.

The previous prime is 139805929. The next prime is 139805969. The reversal of 139805957 is 759508931.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 87590881 + 52215076 = 9359^2 + 7226^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-139805957 is a prime.

It is a super-2 number, since 2×139805957² = 39091411225371698, which contains 22 as substring.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (139805357) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 69902978 + 69902979.

It is an arithmetic number, because the mean of its divisors is an integer number (69902979).

Almost surely, 2^139805957 is an apocalyptic number.

It is an amenable number.

139805957 is a deficient number, since it is larger than the sum of its proper divisors (1).

139805957 is an equidigital number, since it uses as much as digits as its factorization.

139805957 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 340200, while the sum is 47.

The square root of 139805957 is about 11823.9569095967. The cubic root of 139805957 is about 519.0094023292.

The spelling of 139805957 in words is "one hundred thirty-nine million, eight hundred five thousand, nine hundred fifty-seven".