63991698 has 16 divisors (see below), whose sum is σ = 128064576. Its totient is φ = 21317040.

The previous prime is 63991691. The next prime is 63991699. The reversal of 63991698 is 89619936.

It is a self number, because there is not a number n which added to its sum of digits gives 63991698.

It is not an unprimeable number, because it can be changed into a prime (63991691) 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, 12888 + ... + 17148.

It is an arithmetic number, because the mean of its divisors is an integer number (8004036).

Almost surely, 2^63991698 is an apocalyptic number.

63991698 is an abundant number, since it is smaller than the sum of its proper divisors (64072878).

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

63991698 is a wasteful number, since it uses less digits than its factorization.

63991698 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6769.

The product of its digits is 629856, while the sum is 51.

The square root of 63991698 is about 7999.4811081720. The cubic root of 63991698 is about 399.9827034187.

The spelling of 63991698 in words is "sixty-three million, nine hundred ninety-one thousand, six hundred ninety-eight".