139208509457 has 2 divisors, whose sum is σ = 139208509458. Its totient is φ = 139208509456.

The previous prime is 139208509423. The next prime is 139208509469. The reversal of 139208509457 is 754905802931.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 133189232401 + 6019277056 = 364951^2 + 77584^2 .

It is a cyclic number.

It is not a de Polignac number, because 139208509457 - 2⁶ = 139208509393 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 139208509399 and 139208509408.

It is not a weakly prime, because it can be changed into another prime (139208509417) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 69604254728 + 69604254729.

It is an arithmetic number, because the mean of its divisors is an integer number (69604254729).

Almost surely, 2^139208509457 is an apocalyptic number.

It is an amenable number.

139208509457 is a deficient number, since it is larger than the sum of its proper divisors (1).

139208509457 is an equidigital number, since it uses as much as digits as its factorization.

139208509457 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 2721600, while the sum is 53.

The spelling of 139208509457 in words is "one hundred thirty-nine billion, two hundred eight million, five hundred nine thousand, four hundred fifty-seven".