63961993 has 2 divisors, whose sum is σ = 63961994. Its totient is φ = 63961992.

The previous prime is 63961991. The next prime is 63962029. The reversal of 63961993 is 39916936.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 62853184 + 1108809 = 7928^2 + 1053^2 .

It is a cyclic number.

It is not a de Polignac number, because 63961993 - 2¹ = 63961991 is a prime.

It is a super-2 number, since 2×63961993² = 8182273097064098, which contains 22 as substring.

Together with 63961991, it forms a pair of twin primes.

It is not a weakly prime, because it can be changed into another prime (63961991) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 31980996 + 31980997.

It is an arithmetic number, because the mean of its divisors is an integer number (31980997).

Almost surely, 2^63961993 is an apocalyptic number.

It is an amenable number.

63961993 is a deficient number, since it is larger than the sum of its proper divisors (1).

63961993 is an equidigital number, since it uses as much as digits as its factorization.

63961993 is an evil number, because the sum of its binary digits is even.

The product of its digits is 236196, while the sum is 46.

The square root of 63961993 is about 7997.6242097263. The cubic root of 63961993 is about 399.9208030707.

The spelling of 63961993 in words is "sixty-three million, nine hundred sixty-one thousand, nine hundred ninety-three".