39920658640 has 40 divisors (see below), whose sum is σ = 95324066280. Its totient is φ = 15536687616.

The previous prime is 39920658553. The next prime is 39920658671. The reversal of 39920658640 is 4685602993.

It can be written as a sum of positive squares in 4 ways, for example, as 4687867024 + 35232791616 = 68468^2 + 187704^2 .

It is a tau number, because it is divible by the number of its divisors (40).

It is a congruent number.

It is an unprimeable number.

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, 6740395 + ... + 6746314.

It is an arithmetic number, because the mean of its divisors is an integer number (2383101657).

Almost surely, 2^39920658640 is an apocalyptic number.

It is an amenable number.

39920658640 is an abundant number, since it is smaller than the sum of its proper divisors (55403407640).

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

39920658640 is a wasteful number, since it uses less digits than its factorization.

39920658640 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 13486759 (or 13486753 counting only the distinct ones).

The product of its (nonzero) digits is 2799360, while the sum is 52.

The spelling of 39920658640 in words is "thirty-nine billion, nine hundred twenty million, six hundred fifty-eight thousand, six hundred forty".