251205231559 has 4 divisors (see below), whose sum is σ = 265982009904. Its totient is φ = 236428453216.

The previous prime is 251205231493. The next prime is 251205231569. The reversal of 251205231559 is 955132502152.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 251205231559 - 2³⁵ = 216845493191 is a prime.

It is a super-2 number, since 2×251205231559² (a number of 24 digits) contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (251205231569) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 7388389147 + ... + 7388389180.

It is an arithmetic number, because the mean of its divisors is an integer number (66495502476).

Almost surely, 2^251205231559 is an apocalyptic number.

251205231559 is a deficient number, since it is larger than the sum of its proper divisors (14776778345).

251205231559 is a wasteful number, since it uses less digits than its factorization.

251205231559 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 14776778344.

The product of its (nonzero) digits is 135000, while the sum is 40.

The spelling of 251205231559 in words is "two hundred fifty-one billion, two hundred five million, two hundred thirty-one thousand, five hundred fifty-nine".