1639387642 has 16 divisors (see below), whose sum is σ = 2527287840. Its totient is φ = 797125392.

The previous prime is 1639387637. The next prime is 1639387649. The reversal of 1639387642 is 2467839361.

It is not an unprimeable number, because it can be changed into a prime (1639387649) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 21928 + ... + 61315.

It is an arithmetic number, because the mean of its divisors is an integer number (157955490).

Almost surely, 2^1639387642 is an apocalyptic number.

1639387642 is a deficient number, since it is larger than the sum of its proper divisors (887900198).

1639387642 is a wasteful number, since it uses less digits than its factorization.

1639387642 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 83517.

The product of its digits is 1306368, while the sum is 49.

The square root of 1639387642 is about 40489.3522052403. The cubic root of 1639387642 is about 1179.1269137690.

The spelling of 1639387642 in words is "one billion, six hundred thirty-nine million, three hundred eighty-seven thousand, six hundred forty-two".