51664557 has 8 divisors (see below), whose sum is σ = 78726976. Its totient is φ = 29522592.

The previous prime is 51664549. The next prime is 51664567. The reversal of 51664557 is 75546615.

51664557 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 51664557 - 2³ = 51664549 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (51664517) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1230088 + ... + 1230129.

It is an arithmetic number, because the mean of its divisors is an integer number (9840872).

Almost surely, 2^51664557 is an apocalyptic number.

It is an amenable number.

51664557 is a deficient number, since it is larger than the sum of its proper divisors (27062419).

51664557 is a wasteful number, since it uses less digits than its factorization.

51664557 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2460227.

The product of its digits is 126000, while the sum is 39.

The square root of 51664557 is about 7187.8061326110. The cubic root of 51664557 is about 372.4467908924.

The spelling of 51664557 in words is "fifty-one million, six hundred sixty-four thousand, five hundred fifty-seven".