63990640 has 40 divisors (see below), whose sum is σ = 170033760. Its totient is φ = 21939456.

The previous prime is 63990611. The next prime is 63990643. The reversal of 63990640 is 4609936.

63990640 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

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

It is a hoax number, since the sum of its digits (37) coincides with the sum of the digits of its distinct prime factors.

It is a self number, because there is not a number n which added to its sum of digits gives 63990640.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (63990643) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 56575 + ... + 57694.

It is an arithmetic number, because the mean of its divisors is an integer number (4250844).

Almost surely, 2^63990640 is an apocalyptic number.

It is an amenable number.

63990640 is an abundant number, since it is smaller than the sum of its proper divisors (106043120).

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

63990640 is a wasteful number, since it uses less digits than its factorization.

63990640 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 114289 (or 114283 counting only the distinct ones).

The product of its (nonzero) digits is 34992, while the sum is 37.

The square root of 63990640 is about 7999.4149786094. The cubic root of 63990640 is about 399.9804990493.

The spelling of 63990640 in words is "sixty-three million, nine hundred ninety thousand, six hundred forty".