251640027539 has 2 divisors, whose sum is σ = 251640027540. Its totient is φ = 251640027538.

The previous prime is 251640027493. The next prime is 251640027553. The reversal of 251640027539 is 935720046152.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 251640027539 - 2¹² = 251640023443 is a prime.

It is a Sophie Germain prime.

It is a self number, because there is not a number n which added to its sum of digits gives 251640027539.

It is not a weakly prime, because it can be changed into another prime (251640027139) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 125820013769 + 125820013770.

It is an arithmetic number, because the mean of its divisors is an integer number (125820013770).

Almost surely, 2^251640027539 is an apocalyptic number.

251640027539 is a deficient number, since it is larger than the sum of its proper divisors (1).

251640027539 is an equidigital number, since it uses as much as digits as its factorization.

251640027539 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 453600, while the sum is 44.

The spelling of 251640027539 in words is "two hundred fifty-one billion, six hundred forty million, twenty-seven thousand, five hundred thirty-nine".