1639385394 has 8 divisors (see below), whose sum is σ = 3278770800. Its totient is φ = 546461796.

The previous prime is 1639385383. The next prime is 1639385401. The reversal of 1639385394 is 4935839361.

It is a happy number.

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

1639385394 is an admirable number.

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, 136615444 + ... + 136615455.

It is an arithmetic number, because the mean of its divisors is an integer number (409846350).

Almost surely, 2^1639385394 is an apocalyptic number.

1639385394 is a primitive abundant number, since it is smaller than the sum of its proper divisors, none of which is abundant.

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

1639385394 is a wasteful number, since it uses less digits than its factorization.

1639385394 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 273230904.

The product of its digits is 2099520, while the sum is 51.

The square root of 1639385394 is about 40489.3244448460. The cubic root of 1639385394 is about 1179.1263748120.

The spelling of 1639385394 in words is "one billion, six hundred thirty-nine million, three hundred eighty-five thousand, three hundred ninety-four".