1644734161 has 8 divisors (see below), whose sum is σ = 1890198720. Its totient is φ = 1401895248.

The previous prime is 1644734153. The next prime is 1644734167. The reversal of 1644734161 is 1614374461.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 1644734161 - 2³ = 1644734153 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 1644734161.

It is not an unprimeable number, because it can be changed into a prime (1644734167) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 655066 + ... + 657571.

It is an arithmetic number, because the mean of its divisors is an integer number (236274840).

Almost surely, 2^1644734161 is an apocalyptic number.

It is an amenable number.

1644734161 is a deficient number, since it is larger than the sum of its proper divisors (245464559).

1644734161 is a wasteful number, since it uses less digits than its factorization.

1644734161 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1312823.

The product of its digits is 48384, while the sum is 37.

The square root of 1644734161 is about 40555.3222277915. The cubic root of 1644734161 is about 1180.4073478723.

The spelling of 1644734161 in words is "one billion, six hundred forty-four million, seven hundred thirty-four thousand, one hundred sixty-one".