63207991 has 12 divisors (see below), whose sum is σ = 80212680. Its totient is φ = 49252560.

The previous prime is 63207973. The next prime is 63208031. The reversal of 63207991 is 19970236.

It is not a de Polignac number, because 63207991 - 2⁷ = 63207863 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 63207991.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (63207931) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 58096 + ... + 59173.

It is an arithmetic number, because the mean of its divisors is an integer number (6684390).

Almost surely, 2^63207991 is an apocalyptic number.

63207991 is a deficient number, since it is larger than the sum of its proper divisors (17004689).

63207991 is a wasteful number, since it uses less digits than its factorization.

63207991 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 117294 (or 117287 counting only the distinct ones).

The product of its (nonzero) digits is 20412, while the sum is 37.

The square root of 63207991 is about 7950.3453384114. The cubic root of 63207991 is about 398.3431276612.

The spelling of 63207991 in words is "sixty-three million, two hundred seven thousand, nine hundred ninety-one".