51867220 has 12 divisors (see below), whose sum is σ = 108921204. Its totient is φ = 20746880.

The previous prime is 51867217. The next prime is 51867227. The reversal of 51867220 is 2276815.

It can be written as a sum of positive squares in 2 ways, for example, as 29095236 + 22771984 = 5394^2 + 4772^2 .

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (51867227) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1296661 + ... + 1296700.

It is an arithmetic number, because the mean of its divisors is an integer number (9076767).

Almost surely, 2^51867220 is an apocalyptic number.

It is an amenable number.

51867220 is an abundant number, since it is smaller than the sum of its proper divisors (57053984).

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

51867220 is a wasteful number, since it uses less digits than its factorization.

51867220 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2593370 (or 2593368 counting only the distinct ones).

The product of its (nonzero) digits is 6720, while the sum is 31.

The square root of 51867220 is about 7201.8900297075. The cubic root of 51867220 is about 372.9331507682.

The spelling of 51867220 in words is "fifty-one million, eight hundred sixty-seven thousand, two hundred twenty".