63660940639 has 4 divisors (see below), whose sum is σ = 63696527080. Its totient is φ = 63625354200.

The previous prime is 63660940633. The next prime is 63660940667. The reversal of 63660940639 is 93604906636.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 63660940639 - 2³³ = 55071006047 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (63660940633) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 17790537 + ... + 17794114.

It is an arithmetic number, because the mean of its divisors is an integer number (15924131770).

Almost surely, 2^63660940639 is an apocalyptic number.

63660940639 is a deficient number, since it is larger than the sum of its proper divisors (35586441).

63660940639 is a wasteful number, since it uses less digits than its factorization.

63660940639 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 35586440.

The product of its (nonzero) digits is 3779136, while the sum is 52.

The spelling of 63660940639 in words is "sixty-three billion, six hundred sixty million, nine hundred forty thousand, six hundred thirty-nine".