165891264 has 224 divisors, whose sum is σ = 560832000. Its totient is φ = 42900480.

The previous prime is 165891241. The next prime is 165891277. The reversal of 165891264 is 462198561.

It is a tau number, because it is divible by the number of its divisors (224).

It is a super-2 number, since 2×165891264² = 55039822943035392, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (42).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 724302 + ... + 724530.

Almost surely, 2^165891264 is an apocalyptic number.

165891264 is a gapful number since it is divisible by the number (14) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 165891264, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (280416000).

165891264 is an abundant number, since it is smaller than the sum of its proper divisors (394940736).

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

165891264 is a wasteful number, since it uses less digits than its factorization.

165891264 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 276 (or 252 counting only the distinct ones).

The product of its digits is 103680, while the sum is 42.

The square root of 165891264 is about 12879.8782602942. The cubic root of 165891264 is about 549.4664401320.

The spelling of 165891264 in words is "one hundred sixty-five million, eight hundred ninety-one thousand, two hundred sixty-four".