63197991 has 6 divisors (see below), whose sum is σ = 91286000. Its totient is φ = 42131988.

The previous prime is 63197983. The next prime is 63198007. The reversal of 63197991 is 19979136.

63197991 is a `hidden beast` number, since 631 + 9 + 7 + 9 + 9 + 1 = 666.

63197991 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is not a de Polignac number, because 63197991 - 2³ = 63197983 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 (63197191) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 3510991 + ... + 3511008.

Almost surely, 2^63197991 is an apocalyptic number.

63197991 is a deficient number, since it is larger than the sum of its proper divisors (28088009).

63197991 is a wasteful number, since it uses less digits than its factorization.

63197991 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7022005 (or 7022002 counting only the distinct ones).

The product of its digits is 91854, while the sum is 45.

The square root of 63197991 is about 7949.7164100363. The cubic root of 63197991 is about 398.3221195507.

The spelling of 63197991 in words is "sixty-three million, one hundred ninety-seven thousand, nine hundred ninety-one".