251515643043 has 192 divisors, whose sum is σ = 429915340800. Its totient is φ = 130040951040.

The previous prime is 251515642993. The next prime is 251515643083. The reversal of 251515643043 is 340346515152.

It is a happy number.

It is not a de Polignac number, because 251515643043 - 2¹⁰ = 251515642019 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 251515642992 and 251515643010.

It is not an unprimeable number, because it can be changed into a prime (251515643083) by changing a digit.

It is a polite number, since it can be written in 191 ways as a sum of consecutive naturals, for example, 700600498 + ... + 700600856.

It is an arithmetic number, because the mean of its divisors is an integer number (2239142400).

Almost surely, 2^251515643043 is an apocalyptic number.

251515643043 is a gapful number since it is divisible by the number (23) formed by its first and last digit.

251515643043 is a deficient number, since it is larger than the sum of its proper divisors (178399697757).

251515643043 is a wasteful number, since it uses less digits than its factorization.

251515643043 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 582 (or 575 counting only the distinct ones).

The product of its (nonzero) digits is 216000, while the sum is 39.

The spelling of 251515643043 in words is "two hundred fifty-one billion, five hundred fifteen million, six hundred forty-three thousand, forty-three".