251205231569 has 2 divisors, whose sum is σ = 251205231570. Its totient is φ = 251205231568.

The previous prime is 251205231493. The next prime is 251205231587. The reversal of 251205231569 is 965132502152.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 244245500944 + 6959730625 = 494212^2 + 83425^2 .

It is a cyclic number.

It is not a de Polignac number, because 251205231569 - 2¹⁶ = 251205166033 is a prime.

It is a super-2 number, since 2×251205231569² (a number of 24 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (251205261569) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 125602615784 + 125602615785.

It is an arithmetic number, because the mean of its divisors is an integer number (125602615785).

Almost surely, 2^251205231569 is an apocalyptic number.

It is an amenable number.

251205231569 is a deficient number, since it is larger than the sum of its proper divisors (1).

251205231569 is an equidigital number, since it uses as much as digits as its factorization.

251205231569 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 162000, while the sum is 41.

The spelling of 251205231569 in words is "two hundred fifty-one billion, two hundred five million, two hundred thirty-one thousand, five hundred sixty-nine".