1644191044 has 12 divisors (see below), whose sum is σ = 2877889644. Its totient is φ = 821936864.

The previous prime is 1644191039. The next prime is 1644191063. The reversal of 1644191044 is 4401914461.

It can be written as a sum of positive squares in 2 ways, for example, as 164865600 + 1479325444 = 12840^2 + 38462^2 .

It is a super-3 number, since 3×1644191044³ (a number of 29 digits) contains 333 as substring.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 14587 + ... + 59170.

It is an arithmetic number, because the mean of its divisors is an integer number (239824137).

Almost surely, 2^1644191044 is an apocalyptic number.

It is an amenable number.

1644191044 is a deficient number, since it is larger than the sum of its proper divisors (1233698600).

1644191044 is a wasteful number, since it uses less digits than its factorization.

1644191044 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 79334 (or 79332 counting only the distinct ones).

The product of its (nonzero) digits is 13824, while the sum is 34.

The square root of 1644191044 is about 40548.6256733813. The cubic root of 1644191044 is about 1180.2774038986.

The spelling of 1644191044 in words is "one billion, six hundred forty-four million, one hundred ninety-one thousand, forty-four".