165661536 has 24 divisors (see below), whose sum is σ = 434861784. Its totient is φ = 55220480.

The previous prime is 165661523. The next prime is 165661537. The reversal of 165661536 is 635166561.

It is a tau number, because it is divible by the number of its divisors (24).

It is a Smith number, since the sum of its digits (39) coincides with the sum of the digits of its prime factors.

It is a junction number, because it is equal to n+sod(n) for n = 165661494 and 165661503.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (165661537) 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, 862725 + ... + 862916.

It is an arithmetic number, because the mean of its divisors is an integer number (18119241).

Almost surely, 2^165661536 is an apocalyptic number.

165661536 is a gapful number since it is divisible by the number (16) formed by its first and last digit.

It is an amenable number.

165661536 is an abundant number, since it is smaller than the sum of its proper divisors (269200248).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

165661536 is a wasteful number, since it uses less digits than its factorization.

165661536 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1725654 (or 1725646 counting only the distinct ones).

The product of its digits is 97200, while the sum is 39.

The square root of 165661536 is about 12870.9570739708. The cubic root of 165661536 is about 549.2126872913.

The spelling of 165661536 in words is "one hundred sixty-five million, six hundred sixty-one thousand, five hundred thirty-six".