51222400 has 48 divisors (see below), whose sum is σ = 126543240. Its totient is φ = 20487680.

The previous prime is 51222397. The next prime is 51222419. The reversal of 51222400 is 422215.

It is a Harshad number since it is a multiple of its sum of digits (16).

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 4804 + ... + 11203.

Almost surely, 2^51222400 is an apocalyptic number.

51222400 is a gapful number since it is divisible by the number (50) formed by its first and last digit.

It is an amenable number.

51222400 is an abundant number, since it is smaller than the sum of its proper divisors (75320840).

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

51222400 is a wasteful number, since it uses less digits than its factorization.

51222400 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 16031 (or 16014 counting only the distinct ones).

The product of its (nonzero) digits is 160, while the sum is 16.

The square root of 51222400 is about 7156.9826044221. The cubic root of 51222400 is about 371.3812506635.

Adding to 51222400 its reverse (422215), we get a palindrome (51644615).

The spelling of 51222400 in words is "fifty-one million, two hundred twenty-two thousand, four hundred".