51513221500 has 96 divisors (see below), whose sum is σ = 128286377856. Its totient is φ = 17901388800.

The previous prime is 51513221479. The next prime is 51513221519. The reversal of 51513221500 is 512231515.

It is a super-2 number, since 2×51513221500² (a number of 22 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (25).

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 122592 + ... + 343591.

It is an arithmetic number, because the mean of its divisors is an integer number (1336316436).

Almost surely, 2^51513221500 is an apocalyptic number.

51513221500 is a gapful number since it is divisible by the number (50) formed by its first and last digit.

It is an amenable number.

51513221500 is an abundant number, since it is smaller than the sum of its proper divisors (76773156356).

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

51513221500 is a wasteful number, since it uses less digits than its factorization.

51513221500 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 466232 (or 466220 counting only the distinct ones).

The product of its (nonzero) digits is 1500, while the sum is 25.

The spelling of 51513221500 in words is "fifty-one billion, five hundred thirteen million, two hundred twenty-one thousand, five hundred".