155638539317 has 2 divisors, whose sum is σ = 155638539318. Its totient is φ = 155638539316.

The previous prime is 155638539269. The next prime is 155638539341. The reversal of 155638539317 is 713935836551.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 103812195601 + 51826343716 = 322199^2 + 227654^2 .

It is a cyclic number.

It is not a de Polignac number, because 155638539317 - 2¹⁸ = 155638277173 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (155638539367) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 77819269658 + 77819269659.

It is an arithmetic number, because the mean of its divisors is an integer number (77819269659).

Almost surely, 2^155638539317 is an apocalyptic number.

It is an amenable number.

155638539317 is a deficient number, since it is larger than the sum of its proper divisors (1).

155638539317 is an equidigital number, since it uses as much as digits as its factorization.

155638539317 is an evil number, because the sum of its binary digits is even.

The product of its digits is 10206000, while the sum is 56.

The spelling of 155638539317 in words is "one hundred fifty-five billion, six hundred thirty-eight million, five hundred thirty-nine thousand, three hundred seventeen".