1644163412 has 12 divisors (see below), whose sum is σ = 2903683860. Its totient is φ = 814539456.

The previous prime is 1644163397. The next prime is 1644163421. The reversal of 1644163412 is 2143614461.

It can be written as a sum of positive squares in 2 ways, for example, as 1299169936 + 344993476 = 36044^2 + 18574^2 .

It is a super-3 number, since 3×1644163412³ (a number of 29 digits) contains 333 as substring.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1885073 + ... + 1885944.

It is an arithmetic number, because the mean of its divisors is an integer number (241973655).

Almost surely, 2^1644163412 is an apocalyptic number.

It is an amenable number.

1644163412 is a deficient number, since it is larger than the sum of its proper divisors (1259520448).

1644163412 is a wasteful number, since it uses less digits than its factorization.

1644163412 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3771130 (or 3771128 counting only the distinct ones).

The product of its digits is 13824, while the sum is 32.

The square root of 1644163412 is about 40548.2849452354. The cubic root of 1644163412 is about 1180.2707920133.

Adding to 1644163412 its reverse (2143614461), we get a palindrome (3787777873).

The spelling of 1644163412 in words is "one billion, six hundred forty-four million, one hundred sixty-three thousand, four hundred twelve".