251121405607 has 2 divisors, whose sum is σ = 251121405608. Its totient is φ = 251121405606.

The previous prime is 251121405523. The next prime is 251121405707. The reversal of 251121405607 is 706504121152.

It is a weak prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-251121405607 is a prime.

It is a super-2 number, since 2×251121405607² (a number of 24 digits) contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (251121405707) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 125560702803 + 125560702804.

It is an arithmetic number, because the mean of its divisors is an integer number (125560702804).

Almost surely, 2^251121405607 is an apocalyptic number.

251121405607 is a deficient number, since it is larger than the sum of its proper divisors (1).

251121405607 is an equidigital number, since it uses as much as digits as its factorization.

251121405607 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 16800, while the sum is 34.

Adding to 251121405607 its reverse (706504121152), we get a palindrome (957625526759).

The spelling of 251121405607 in words is "two hundred fifty-one billion, one hundred twenty-one million, four hundred five thousand, six hundred seven".