1644117516 has 18 divisors (see below), whose sum is σ = 4155963812. Its totient is φ = 548039160.

The previous prime is 1644117499. The next prime is 1644117521. The reversal of 1644117516 is 6157114461.

1644117516 is a `hidden beast` number, since 1 + 644 + 1 + 1 + 7 + 5 + 1 + 6 = 666.

It is a tau number, because it is divible by the number of its divisors (18).

It is a super-3 number, since 3×1644117516³ (a number of 29 digits) contains 333 as substring.

It is a Harshad number since it is a multiple of its sum of digits (36), and also a Moran number because the ratio is a prime number: 45669931 = 1644117516 / (1 + 6 + 4 + 4 + 1 + 1 + 7 + 5 + 1 + 6).

It is a zygodrome in base 2.

It is an unprimeable number.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 22834930 + ... + 22835001.

Almost surely, 2^1644117516 is an apocalyptic number.

It is an amenable number.

1644117516 is an abundant number, since it is smaller than the sum of its proper divisors (2511846296).

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

1644117516 is a wasteful number, since it uses less digits than its factorization.

1644117516 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 45669941 (or 45669936 counting only the distinct ones).

The product of its digits is 20160, while the sum is 36.

The square root of 1644117516 is about 40547.7189987304. The cubic root of 1644117516 is about 1180.2598096880.

The spelling of 1644117516 in words is "one billion, six hundred forty-four million, one hundred seventeen thousand, five hundred sixteen".