251220312413540 has 48 divisors (see below), whose sum is σ = 528387334110720. Its totient is φ = 100331091557760.

The previous prime is 251220312413491. The next prime is 251220312413557. The reversal of 251220312413540 is 45314213022152.

It is a super-2 number, since 2×251220312413540² (a number of 30 digits) contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 251220312413540.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 82205369 + ... + 85206591.

It is an arithmetic number, because the mean of its divisors is an integer number (11008069460640).

Almost surely, 2^{251220312413540} is an apocalyptic number.

251220312413540 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

251220312413540 is an abundant number, since it is smaller than the sum of its proper divisors (277167021697180).

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

251220312413540 is a wasteful number, since it uses less digits than its factorization.

251220312413540 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3007772 (or 3007770 counting only the distinct ones).

The product of its (nonzero) digits is 57600, while the sum is 35.

Adding to 251220312413540 its reverse (45314213022152), we get a palindrome (296534525435692).

The spelling of 251220312413540 in words is "two hundred fifty-one trillion, two hundred twenty billion, three hundred twelve million, four hundred thirteen thousand, five hundred forty".