51220800 has 126 divisors (see below), whose sum is σ = 182101998. Its totient is φ = 13655040.

The previous prime is 51220777. The next prime is 51220823. The reversal of 51220800 is 802215.

It is an interprime number because it is at equal distance from previous prime (51220777) and next prime (51220823).

It can be written as a sum of positive squares in 3 ways, for example, as 69696 + 51151104 = 264^2 + 7152^2 .

It is a Harshad number since it is a multiple of its sum of digits (18).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 17 ways as a sum of consecutive naturals, for example, 12622 + ... + 16178.

Almost surely, 2^51220800 is an apocalyptic number.

51220800 is a gapful number since it is divisible by the number (50) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 51220800, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (91050999).

51220800 is an abundant number, since it is smaller than the sum of its proper divisors (130881198).

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

51220800 is a wasteful number, since it uses less digits than its factorization.

51220800 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3585 (or 3567 counting only the distinct ones).

The product of its (nonzero) digits is 160, while the sum is 18.

The square root of 51220800 is about 7156.8708245993. The cubic root of 51220800 is about 371.3773837603.

It can be divided in two parts, 512 and 20800, that added together give a palindrome (21312).

The spelling of 51220800 in words is "fifty-one million, two hundred twenty thousand, eight hundred".