51321212400 has 120 divisors (see below), whose sum is σ = 166480257280. Its totient is φ = 13512395520.

The previous prime is 51321212389. The next prime is 51321212407. The reversal of 51321212400 is 421212315.

It is a tau number, because it is divible by the number of its divisors (120).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (51321212407) by changing a digit.

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 23 ways as a sum of consecutive naturals, for example, 175882 + ... + 365481.

Almost surely, 2^51321212400 is an apocalyptic number.

51321212400 is a gapful number since it is divisible by the number (50) formed by its first and last digit.

It is an amenable number.

51321212400 is an abundant number, since it is smaller than the sum of its proper divisors (115159044880).

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

51321212400 is a wasteful number, since it uses less digits than its factorization.

51321212400 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 541463 (or 541452 counting only the distinct ones).

The product of its (nonzero) digits is 480, while the sum is 21.

Adding to 51321212400 its reverse (421212315), we get a palindrome (51742424715).

The spelling of 51321212400 in words is "fifty-one billion, three hundred twenty-one million, two hundred twelve thousand, four hundred".