1639972389 has 8 divisors (see below), whose sum is σ = 2385414432. Its totient is φ = 993922640.

The previous prime is 1639972379. The next prime is 1639972393. The reversal of 1639972389 is 9832799361.

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 1639972389 - 2¹¹ = 1639970341 is a prime.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1639972309) 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, 24848034 + ... + 24848099.

It is an arithmetic number, because the mean of its divisors is an integer number (298176804).

Almost surely, 2^1639972389 is an apocalyptic number.

It is an amenable number.

1639972389 is a deficient number, since it is larger than the sum of its proper divisors (745442043).

1639972389 is a wasteful number, since it uses less digits than its factorization.

1639972389 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 49696147.

The product of its digits is 4408992, while the sum is 57.

The square root of 1639972389 is about 40496.5725586746. The cubic root of 1639972389 is about 1179.2670898825.

It can be divided in two parts, 16399 and 72389, that added together give a palindrome (88788).

The spelling of 1639972389 in words is "one billion, six hundred thirty-nine million, nine hundred seventy-two thousand, three hundred eighty-nine".