51666616 has 8 divisors (see below), whose sum is σ = 96874920. Its totient is φ = 25833304.

The previous prime is 51666577. The next prime is 51666617. The reversal of 51666616 is 61666615.

51666616 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a tau number, because it is divible by the number of its divisors (8).

It is a hoax number, since the sum of its digits (37) coincides with the sum of the digits of its distinct prime factors.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (51666617) 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 as a sum of consecutive naturals, namely, 3229156 + ... + 3229171.

It is an arithmetic number, because the mean of its divisors is an integer number (12109365).

Almost surely, 2^51666616 is an apocalyptic number.

It is an amenable number.

51666616 is a deficient number, since it is larger than the sum of its proper divisors (45208304).

51666616 is a wasteful number, since it uses less digits than its factorization.

51666616 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6458333 (or 6458329 counting only the distinct ones).

The product of its digits is 38880, while the sum is 37.

The square root of 51666616 is about 7187.9493598661. The cubic root of 51666616 is about 372.4517385638.

Subtracting 51666616 from its reverse (61666615), we obtain a palindrome (9999999).

The spelling of 51666616 in words is "fifty-one million, six hundred sixty-six thousand, six hundred sixteen".