1644673465 has 16 divisors (see below), whose sum is σ = 2006363520. Its totient is φ = 1293994240.

The previous prime is 1644673451. The next prime is 1644673487. The reversal of 1644673465 is 5643764461.

It is not a de Polignac number, because 1644673465 - 2²⁵ = 1611119033 is a prime.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 143217 + ... + 154273.

It is an arithmetic number, because the mean of its divisors is an integer number (125397720).

Almost surely, 2^1644673465 is an apocalyptic number.

It is an amenable number.

1644673465 is a deficient number, since it is larger than the sum of its proper divisors (361690055).

1644673465 is a wasteful number, since it uses less digits than its factorization.

1644673465 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 11552.

The product of its digits is 1451520, while the sum is 46.

The square root of 1644673465 is about 40554.5739097330. The cubic root of 1644673465 is about 1180.3928274131.

The spelling of 1644673465 in words is "one billion, six hundred forty-four million, six hundred seventy-three thousand, four hundred sixty-five".