63991078191 has 20 divisors (see below), whose sum is σ = 96279337000. Its totient is φ = 42353799696.

The previous prime is 63991078159. The next prime is 63991078211. The reversal of 63991078191 is 19187019936.

It is a happy number.

It is not a de Polignac number, because 63991078191 - 2⁵ = 63991078159 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 (63991078111) by changing a digit.

It is a polite number, since it can be written in 19 ways as a sum of consecutive naturals, for example, 2830516 + ... + 2853033.

It is an arithmetic number, because the mean of its divisors is an integer number (4813966850).

Almost surely, 2^63991078191 is an apocalyptic number.

63991078191 is a deficient number, since it is larger than the sum of its proper divisors (32288258809).

63991078191 is a wasteful number, since it uses less digits than its factorization.

63991078191 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5683700 (or 5683691 counting only the distinct ones).

The product of its (nonzero) digits is 734832, while the sum is 54.

The spelling of 63991078191 in words is "sixty-three billion, nine hundred ninety-one million, seventy-eight thousand, one hundred ninety-one".