165373881 has 4 divisors (see below), whose sum is σ = 220498512. Its totient is φ = 110249252.

The previous prime is 165373861. The next prime is 165373903. The reversal of 165373881 is 188373561.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 165373881 - 2⁵ = 165373849 is a prime.

It is a super-2 number, since 2×165373881² = 54697041034004322, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (165373811) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 27562311 + ... + 27562316.

It is an arithmetic number, because the mean of its divisors is an integer number (55124628).

Almost surely, 2^165373881 is an apocalyptic number.

It is an amenable number.

165373881 is a deficient number, since it is larger than the sum of its proper divisors (55124631).

165373881 is an equidigital number, since it uses as much as digits as its factorization.

165373881 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 55124630.

The product of its digits is 120960, while the sum is 42.

The square root of 165373881 is about 12859.7776419346. Note that the first 3 decimals coincide. The cubic root of 165373881 is about 548.8946184770.

The spelling of 165373881 in words is "one hundred sixty-five million, three hundred seventy-three thousand, eight hundred eighty-one".