63978915501 has 8 divisors (see below), whose sum is σ = 94783578560. Its totient is φ = 42652610316.

The previous prime is 63978915467. The next prime is 63978915503. The reversal of 63978915501 is 10551987936.

63978915501 is a `hidden beast` number, since 6 + 3 + 9 + 7 + 89 + 1 + 550 + 1 = 666.

It is not a de Polignac number, because 63978915501 - 2²¹ = 63976818349 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (63978915503) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1184794705 + ... + 1184794758.

It is an arithmetic number, because the mean of its divisors is an integer number (11847947320).

Almost surely, 2^63978915501 is an apocalyptic number.

It is an amenable number.

63978915501 is a deficient number, since it is larger than the sum of its proper divisors (30804663059).

63978915501 is a wasteful number, since it uses less digits than its factorization.

63978915501 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2369589472 (or 2369589466 counting only the distinct ones).

The product of its (nonzero) digits is 2041200, while the sum is 54.

The spelling of 63978915501 in words is "sixty-three billion, nine hundred seventy-eight million, nine hundred fifteen thousand, five hundred one".