639490946394 has 16 divisors (see below), whose sum is σ = 1278991245600. Its totient is φ = 213162090000.

The previous prime is 639490946363. The next prime is 639490946461. The reversal of 639490946394 is 493649094936.

It is a Curzon number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 760144 + ... + 1362644.

It is an arithmetic number, because the mean of its divisors is an integer number (79936952850).

Almost surely, 2^639490946394 is an apocalyptic number.

639490946394 is an abundant number, since it is smaller than the sum of its proper divisors (639500299206).

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

639490946394 is a wasteful number, since it uses less digits than its factorization.

639490946394 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 779405.

The product of its (nonzero) digits is 136048896, while the sum is 66.

The spelling of 639490946394 in words is "six hundred thirty-nine billion, four hundred ninety million, nine hundred forty-six thousand, three hundred ninety-four".