164664640 has 224 divisors, whose sum is σ = 487192320. Its totient is φ = 51757056.

The previous prime is 164664637. The next prime is 164664671. The reversal of 164664640 is 46466461.

It is a happy number.

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

It is a super-2 number, since 2×164664640² = 54228887332659200, which contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 164664640.

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, 2255644 + ... + 2255716.

Almost surely, 2^164664640 is an apocalyptic number.

164664640 is a gapful number since it is divisible by the number (10) 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 164664640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (243596160).

164664640 is an abundant number, since it is smaller than the sum of its proper divisors (322527680).

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

164664640 is a wasteful number, since it uses less digits than its factorization.

164664640 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 169 (or 159 counting only the distinct ones).

The product of its (nonzero) digits is 82944, while the sum is 37.

The square root of 164664640 is about 12832.1720686718. The cubic root of 164664640 is about 548.1088103325.

The spelling of 164664640 in words is "one hundred sixty-four million, six hundred sixty-four thousand, six hundred forty".