51665399356615 has 32 divisors (see below), whose sum is σ = 71195076541440. Its totient is φ = 35596887638400.

The previous prime is 51665399356603. The next prime is 51665399356619.

51665399356615 is nontrivially palindromic in base 10.

It is not a de Polignac number, because 51665399356615 - 2²⁹ = 51664862485703 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (51665399356619) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 194192130 + ... + 194458000.

It is an arithmetic number, because the mean of its divisors is an integer number (2224846141920).

Almost surely, 2^{51665399356615} is an apocalyptic number.

51665399356615 is a gapful number since it is divisible by the number (55) formed by its first and last digit.

51665399356615 is a deficient number, since it is larger than the sum of its proper divisors (19529677184825).

51665399356615 is a wasteful number, since it uses less digits than its factorization.

51665399356615 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 451863.

The product of its digits is 590490000, while the sum is 70.

The spelling of 51665399356615 in words is "fifty-one trillion, six hundred sixty-five billion, three hundred ninety-nine million, three hundred fifty-six thousand, six hundred fifteen".