251555675281 has 2 divisors, whose sum is σ = 251555675282. Its totient is φ = 251555675280.

The previous prime is 251555675263. The next prime is 251555675297. The reversal of 251555675281 is 182576555152.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 214406967681 + 37148707600 = 463041^2 + 192740^2 .

It is a cyclic number.

It is not a de Polignac number, because 251555675281 - 2⁷ = 251555675153 is a prime.

It is a super-2 number, since 2×251555675281² (a number of 24 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (251555675251) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 125777837640 + 125777837641.

It is an arithmetic number, because the mean of its divisors is an integer number (125777837641).

Almost surely, 2^251555675281 is an apocalyptic number.

It is an amenable number.

251555675281 is a deficient number, since it is larger than the sum of its proper divisors (1).

251555675281 is an equidigital number, since it uses as much as digits as its factorization.

251555675281 is an evil number, because the sum of its binary digits is even.

The product of its digits is 4200000, while the sum is 52.

The spelling of 251555675281 in words is "two hundred fifty-one billion, five hundred fifty-five million, six hundred seventy-five thousand, two hundred eighty-one".