251315402430 has 128 divisors (see below), whose sum is σ = 619670445696. Its totient is φ = 65208729600.

The previous prime is 251315402423. The next prime is 251315402431. The reversal of 251315402430 is 34204513152.

It is a Harshad number since it is a multiple of its sum of digits (30).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (251315402431) by changing a digit.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 157366392 + ... + 157367988.

It is an arithmetic number, because the mean of its divisors is an integer number (4841175357).

Almost surely, 2^251315402430 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 251315402430, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (309835222848).

251315402430 is an abundant number, since it is smaller than the sum of its proper divisors (368355043266).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

251315402430 is a wasteful number, since it uses less digits than its factorization.

251315402430 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2542.

The product of its (nonzero) digits is 14400, while the sum is 30.

Adding to 251315402430 its reverse (34204513152), we get a palindrome (285519915582).

The spelling of 251315402430 in words is "two hundred fifty-one billion, three hundred fifteen million, four hundred two thousand, four hundred thirty".