165969864 has 128 divisors (see below), whose sum is σ = 498864000. Its totient is φ = 50948352.

The previous prime is 165969833. The next prime is 165969887. The reversal of 165969864 is 468969561.

165969864 = T₃₀₅ + T₃₀₆ + ... + T₁₀₀₇.

It is a happy number.

It is a Harshad number since it is a multiple of its sum of digits (54).

It is a self number, because there is not a number n which added to its sum of digits gives 165969864.

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, 151302 + ... + 152394.

It is an arithmetic number, because the mean of its divisors is an integer number (3897375).

Almost surely, 2^165969864 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 165969864, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (249432000).

165969864 is an abundant number, since it is smaller than the sum of its proper divisors (332894136).

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

165969864 is a wasteful number, since it uses less digits than its factorization.

165969864 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1164 (or 1154 counting only the distinct ones).

The product of its digits is 2799360, while the sum is 54.

The square root of 165969864 is about 12882.9291700296. The cubic root of 165969864 is about 549.5532062904.

The spelling of 165969864 in words is "one hundred sixty-five million, nine hundred sixty-nine thousand, eight hundred sixty-four".