161555066516615 has 32 divisors (see below), whose sum is σ = 201547888778880. Its totient is φ = 124219360921600.

The previous prime is 161555066516611. The next prime is 161555066516633. The reversal of 161555066516615 is 516615660555161.

It is not a de Polignac number, because 161555066516615 - 2² = 161555066516611 is a prime.

It is a super-2 number, since 2×161555066516615² (a number of 29 digits) contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (161555066516611) 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, 14455877 + ... + 23066913.

It is an arithmetic number, because the mean of its divisors is an integer number (6298371524340).

Almost surely, 2^{161555066516615} is an apocalyptic number.

161555066516615 is a deficient number, since it is larger than the sum of its proper divisors (39992822262265).

161555066516615 is a wasteful number, since it uses less digits than its factorization.

161555066516615 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8612443.

The product of its (nonzero) digits is 24300000, while the sum is 59.

The spelling of 161555066516615 in words is "one hundred sixty-one trillion, five hundred fifty-five billion, sixty-six million, five hundred sixteen thousand, six hundred fifteen".