1644338160 has 60 divisors (see below), whose sum is σ = 5522238072. Its totient is φ = 438489984.

The previous prime is 1644338131. The next prime is 1644338161. The reversal of 1644338160 is 618334461.

It is a happy number.

1644338160 is a `hidden beast` number, since 1 + 64 + 433 + 8 + 160 = 666.

It is a tau number, because it is divible by the number of its divisors (60).

It is a super-3 number, since 3×1644338160³ (a number of 29 digits) contains 333 as substring.

It is a hoax number, since the sum of its digits (36) coincides with the sum of the digits of its distinct prime factors.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1644338161) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 1141182 + ... + 1142621.

Almost surely, 2^1644338160 is an apocalyptic number.

1644338160 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1644338160 is an abundant number, since it is smaller than the sum of its proper divisors (3877899912).

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

1644338160 is a wasteful number, since it uses less digits than its factorization.

1644338160 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2283822 (or 2283813 counting only the distinct ones).

The product of its (nonzero) digits is 41472, while the sum is 36.

The square root of 1644338160 is about 40550.4397016851. The cubic root of 1644338160 is about 1180.3126051024.

The spelling of 1644338160 in words is "one billion, six hundred forty-four million, three hundred thirty-eight thousand, one hundred sixty".