51515551651 has 8 divisors (see below), whose sum is σ = 52302816720. Its totient is φ = 50732253312.

The previous prime is 51515551643. The next prime is 51515551679. The reversal of 51515551651 is 15615551515.

It is a happy number.

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

It is a cyclic number.

It is not a de Polignac number, because 51515551651 - 2³ = 51515551643 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (51515551621) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 965506 + ... + 1017463.

It is an arithmetic number, because the mean of its divisors is an integer number (6537852090).

Almost surely, 2^51515551651 is an apocalyptic number.

51515551651 is a deficient number, since it is larger than the sum of its proper divisors (787265069).

51515551651 is a wasteful number, since it uses less digits than its factorization.

51515551651 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1983365.

The product of its digits is 93750, while the sum is 40.

The spelling of 51515551651 in words is "fifty-one billion, five hundred fifteen million, five hundred fifty-one thousand, six hundred fifty-one".