1644272123 has 16 divisors (see below), whose sum is σ = 1798362720. Its totient is φ = 1494291456.

The previous prime is 1644272107. The next prime is 1644272129. The reversal of 1644272123 is 3212724461.

It is a cyclic number.

It is not a de Polignac number, because 1644272123 - 2⁴ = 1644272107 is a prime.

It is a super-3 number, since 3×1644272123³ (a number of 29 digits) contains 333 as substring.

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 1644272123.

It is not an unprimeable number, because it can be changed into a prime (1644272129) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 245108 + ... + 251726.

It is an arithmetic number, because the mean of its divisors is an integer number (112397670).

Almost surely, 2^1644272123 is an apocalyptic number.

1644272123 is a gapful number since it is divisible by the number (13) formed by its first and last digit.

1644272123 is a deficient number, since it is larger than the sum of its proper divisors (154090597).

1644272123 is a wasteful number, since it uses less digits than its factorization.

1644272123 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6926.

The product of its digits is 16128, while the sum is 32.

The square root of 1644272123 is about 40549.6254360013. The cubic root of 1644272123 is about 1180.2968043487.

Adding to 1644272123 its reverse (3212724461), we get a palindrome (4856996584).

The spelling of 1644272123 in words is "one billion, six hundred forty-four million, two hundred seventy-two thousand, one hundred twenty-three".