1394664639 has 8 divisors (see below), whose sum is σ = 1940403072. Its totient is φ = 889351320.

The previous prime is 1394664637. The next prime is 1394664653. The reversal of 1394664639 is 9364664931.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 1394664639 - 2¹ = 1394664637 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 1394664591 and 1394664600.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1394664637) 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, 10106197 + ... + 10106334.

It is an arithmetic number, because the mean of its divisors is an integer number (242550384).

Almost surely, 2^1394664639 is an apocalyptic number.

1394664639 is a deficient number, since it is larger than the sum of its proper divisors (545738433).

1394664639 is a wasteful number, since it uses less digits than its factorization.

1394664639 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 20212557.

The product of its digits is 2519424, while the sum is 51.

The square root of 1394664639 is about 37345.2090501580. The cubic root of 1394664639 is about 1117.2660355303.

The spelling of 1394664639 in words is "one billion, three hundred ninety-four million, six hundred sixty-four thousand, six hundred thirty-nine".