165209941943 has 16 divisors (see below), whose sum is σ = 179198417664. Its totient is φ = 151739322240.

The previous prime is 165209941931. The next prime is 165209941951. The reversal of 165209941943 is 349149902561.

It is a cyclic number.

It is not a de Polignac number, because 165209941943 - 2²⁴ = 165193164727 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (165209941243) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 555923 + ... + 799668.

It is an arithmetic number, because the mean of its divisors is an integer number (11199901104).

Almost surely, 2^165209941943 is an apocalyptic number.

165209941943 is a deficient number, since it is larger than the sum of its proper divisors (13988475721).

165209941943 is a wasteful number, since it uses less digits than its factorization.

165209941943 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1355782.

The product of its (nonzero) digits is 2099520, while the sum is 53.

The spelling of 165209941943 in words is "one hundred sixty-five billion, two hundred nine million, nine hundred forty-one thousand, nine hundred forty-three".