251555325120 has 672 divisors, whose sum is σ = 986656619520. Its totient is φ = 58282721280.

The previous prime is 251555325079. The next prime is 251555325121. The reversal of 251555325120 is 21523555152.

251555325120 is a `hidden beast` number, since 2 + 5 + 1 + 55 + 532 + 51 + 20 = 666.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is not an unprimeable number, because it can be changed into a prime (251555325121) by changing a digit.

It is a polite number, since it can be written in 95 ways as a sum of consecutive naturals, for example, 64023316 + ... + 64027244.

Almost surely, 2^251555325120 is an apocalyptic number.

251555325120 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 251555325120, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (493328309760).

251555325120 is an abundant number, since it is smaller than the sum of its proper divisors (735101294400).

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

251555325120 is a wasteful number, since it uses less digits than its factorization.

251555325120 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4053 (or 4040 counting only the distinct ones).

The product of its (nonzero) digits is 75000, while the sum is 36.

It can be divided in two parts, 251555 and 325120, that added together give a palindrome (576675).

The spelling of 251555325120 in words is "two hundred fifty-one billion, five hundred fifty-five million, three hundred twenty-five thousand, one hundred twenty".