165809998 has 8 divisors (see below), whose sum is σ = 261805320. Its totient is φ = 78541560.

The previous prime is 165809971. The next prime is 165809999. The reversal of 165809998 is 899908561.

165809998 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (165809999) 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, 2181673 + ... + 2181748.

It is an arithmetic number, because the mean of its divisors is an integer number (32725665).

Almost surely, 2^165809998 is an apocalyptic number.

165809998 is a deficient number, since it is larger than the sum of its proper divisors (95995322).

165809998 is a wasteful number, since it uses less digits than its factorization.

165809998 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4363442.

The product of its (nonzero) digits is 1399680, while the sum is 55.

The square root of 165809998 is about 12876.7231079961. The cubic root of 165809998 is about 549.3767021673.

The spelling of 165809998 in words is "one hundred sixty-five million, eight hundred nine thousand, nine hundred ninety-eight".