2151315123665 has 16 divisors (see below), whose sum is σ = 2585407549968. Its totient is φ = 1718500014336.

The previous prime is 2151315123647. The next prime is 2151315123677. The reversal of 2151315123665 is 5663215131512.

It can be written as a sum of positive squares in 8 ways, for example, as 466542275521 + 1684772848144 = 683039^2 + 1297988^2 .

It is a cyclic number.

It is not a de Polignac number, because 2151315123665 - 2⁸ = 2151315123409 is a prime.

It is a super-2 number, since 2×2151315123665² (a number of 25 digits) contains 22 as substring.

It is a Duffinian number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 21489707 + ... + 21589583.

It is an arithmetic number, because the mean of its divisors is an integer number (161587971873).

Almost surely, 2^{2151315123665} is an apocalyptic number.

It is an amenable number.

2151315123665 is a deficient number, since it is larger than the sum of its proper divisors (434092426303).

2151315123665 is an equidigital number, since it uses as much as digits as its factorization.

2151315123665 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 106228.

The product of its digits is 162000, while the sum is 41.

The spelling of 2151315123665 in words is "two trillion, one hundred fifty-one billion, three hundred fifteen million, one hundred twenty-three thousand, six hundred sixty-five".