161895535999 has 8 divisors (see below), whose sum is σ = 167917343328. Its totient is φ = 155960373600.

The previous prime is 161895535987. The next prime is 161895536021. The reversal of 161895535999 is 999535598161.

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 161895535999 - 2²³ = 161887147391 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (161895535799) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 21657427 + ... + 21664900.

It is an arithmetic number, because the mean of its divisors is an integer number (20989667916).

Almost surely, 2^161895535999 is an apocalyptic number.

161895535999 is a deficient number, since it is larger than the sum of its proper divisors (6021807329).

161895535999 is a wasteful number, since it uses less digits than its factorization.

161895535999 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 43322465.

The product of its digits is 118098000, while the sum is 70.

The spelling of 161895535999 in words is "one hundred sixty-one billion, eight hundred ninety-five million, five hundred thirty-five thousand, nine hundred ninety-nine".