165515781236455 has 8 divisors (see below), whose sum is σ = 213897317290272. Its totient is φ = 122227038451488.

The previous prime is 165515781236389. The next prime is 165515781236471. The reversal of 165515781236455 is 554632187515561.

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 165515781236455 - 2⁷ = 165515781236327 is a prime.

It is a Duffinian number.

It is a congruent number.

It is an unprimeable number.

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, 1273198317139 + ... + 1273198317268.

It is an arithmetic number, because the mean of its divisors is an integer number (26737164661284).

Almost surely, 2^{165515781236455} is an apocalyptic number.

165515781236455 is a deficient number, since it is larger than the sum of its proper divisors (48381536053817).

165515781236455 is a wasteful number, since it uses less digits than its factorization.

165515781236455 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2546396634425.

The product of its digits is 151200000, while the sum is 64.

The spelling of 165515781236455 in words is "one hundred sixty-five trillion, five hundred fifteen billion, seven hundred eighty-one million, two hundred thirty-six thousand, four hundred fifty-five".