51664230 has 112 divisors (see below), whose sum is σ = 147161520. Its totient is φ = 13017024.

The previous prime is 51664219. The next prime is 51664231. The reversal of 51664230 is 3246615.

51664230 is a `hidden beast` number, since 5 + 16 + 642 + 3 + 0 = 666.

It is a super-2 number, since 2×51664230² = 5338385322985800, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a junction number, because it is equal to n+sod(n) for n = 51664194 and 51664203.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (51664231) by changing a digit.

It is a polite number, since it can be written in 55 ways as a sum of consecutive naturals, for example, 138324 + ... + 138696.

Almost surely, 2^51664230 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 51664230, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (73580760).

51664230 is an abundant number, since it is smaller than the sum of its proper divisors (95497290).

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

51664230 is a wasteful number, since it uses less digits than its factorization.

51664230 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 417 (or 402 counting only the distinct ones).

The product of its (nonzero) digits is 4320, while the sum is 27.

The square root of 51664230 is about 7187.7833857177. The cubic root of 51664230 is about 372.4460051160.

It can be divided in two parts, 516 and 64230, that added together give a palindrome (64746).

The spelling of 51664230 in words is "fifty-one million, six hundred sixty-four thousand, two hundred thirty".