251533122397 has 2 divisors, whose sum is σ = 251533122398. Its totient is φ = 251533122396.

The previous prime is 251533122329. The next prime is 251533122419. The reversal of 251533122397 is 793221335152.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 153982468836 + 97550653561 = 392406^2 + 312331^2 .

It is a cyclic number.

It is not a de Polignac number, because 251533122397 - 2¹⁵ = 251533089629 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (251533122097) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 125766561198 + 125766561199.

It is an arithmetic number, because the mean of its divisors is an integer number (125766561199).

Almost surely, 2^251533122397 is an apocalyptic number.

It is an amenable number.

251533122397 is a deficient number, since it is larger than the sum of its proper divisors (1).

251533122397 is an equidigital number, since it uses as much as digits as its factorization.

251533122397 is an evil number, because the sum of its binary digits is even.

The product of its digits is 340200, while the sum is 43.

The spelling of 251533122397 in words is "two hundred fifty-one billion, five hundred thirty-three million, one hundred twenty-two thousand, three hundred ninety-seven".