165166155551505 has 32 divisors (see below), whose sum is σ = 266993265369600. Its totient is φ = 87179498053632.

The previous prime is 165166155551483. The next prime is 165166155551519. The reversal of 165166155551505 is 505155551661561.

It is not a de Polignac number, because 165166155551505 - 2¹² = 165166155547409 is a prime.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 138035241 + ... + 139226649.

It is an arithmetic number, because the mean of its divisors is an integer number (8343539542800).

Almost surely, 2^{165166155551505} is an apocalyptic number.

165166155551505 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

It is an amenable number.

165166155551505 is a deficient number, since it is larger than the sum of its proper divisors (101827109818095).

165166155551505 is a wasteful number, since it uses less digits than its factorization.

165166155551505 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1286793.

The product of its (nonzero) digits is 16875000, while the sum is 57.

The spelling of 165166155551505 in words is "one hundred sixty-five trillion, one hundred sixty-six billion, one hundred fifty-five million, five hundred fifty-one thousand, five hundred five".