51615977 has 4 divisors (see below), whose sum is σ = 58989696. Its totient is φ = 44242260.

The previous prime is 51615959. The next prime is 51616009. The reversal of 51615977 is 77951615.

51615977 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 51615977 - 2¹⁸ = 51353833 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (51615947) 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 3 ways as a sum of consecutive naturals, for example, 3686849 + ... + 3686862.

It is an arithmetic number, because the mean of its divisors is an integer number (14747424).

Almost surely, 2^51615977 is an apocalyptic number.

It is an amenable number.

51615977 is a deficient number, since it is larger than the sum of its proper divisors (7373719).

51615977 is an equidigital number, since it uses as much as digits as its factorization.

51615977 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7373718.

The product of its digits is 66150, while the sum is 41.

The square root of 51615977 is about 7184.4260035162. The cubic root of 51615977 is about 372.3300174846.

The spelling of 51615977 in words is "fifty-one million, six hundred fifteen thousand, nine hundred seventy-seven".