51664500 has 192 divisors, whose sum is σ = 172972800. Its totient is φ = 13305600.

The previous prime is 51664451. The next prime is 51664517. The reversal of 51664500 is 546615.

It is a happy number.

51664500 is a `hidden beast` number, since 5 + 16 + 645 + 0 + 0 = 666.

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

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 580456 + ... + 580544.

It is an arithmetic number, because the mean of its divisors is an integer number (900900).

Almost surely, 2^51664500 is an apocalyptic number.

51664500 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 51664500, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (86486400).

51664500 is an abundant number, since it is smaller than the sum of its proper divisors (121308300).

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

51664500 is a wasteful number, since it uses less digits than its factorization.

51664500 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 160 (or 142 counting only the distinct ones).

The product of its (nonzero) digits is 3600, while the sum is 27.

The square root of 51664500 is about 7187.8021675614. The cubic root of 51664500 is about 372.4466539224.

The spelling of 51664500 in words is "fifty-one million, six hundred sixty-four thousand, five hundred".