251261602120 has 32 divisors (see below), whose sum is σ = 569082582720. Its totient is φ = 99839044800.

The previous prime is 251261602099. The next prime is 251261602121. The reversal of 251261602120 is 21206162152.

It is not an unprimeable number, because it can be changed into a prime (251261602121) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 20793762 + ... + 20805841.

It is an arithmetic number, because the mean of its divisors is an integer number (17783830710).

Almost surely, 2^251261602120 is an apocalyptic number.

251261602120 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

251261602120 is an abundant number, since it is smaller than the sum of its proper divisors (317820980600).

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

251261602120 is a wasteful number, since it uses less digits than its factorization.

251261602120 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 41599765 (or 41599761 counting only the distinct ones).

The product of its (nonzero) digits is 2880, while the sum is 28.

Adding to 251261602120 its reverse (21206162152), we get a palindrome (272467764272).

The spelling of 251261602120 in words is "two hundred fifty-one billion, two hundred sixty-one million, six hundred two thousand, one hundred twenty".