63355681 has 2 divisors, whose sum is σ = 63355682. Its totient is φ = 63355680.

The previous prime is 63355627. The next prime is 63355693. The reversal of 63355681 is 18655336.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 63345681 + 10000 = 7959^2 + 100^2 .

It is a cyclic number.

It is not a de Polignac number, because 63355681 - 2⁷ = 63355553 is a prime.

It is a super-2 number, since 2×63355681² = 8027884629947522, which contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 63355681.

It is not a weakly prime, because it can be changed into another prime (63355781) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 31677840 + 31677841.

It is an arithmetic number, because the mean of its divisors is an integer number (31677841).

Almost surely, 2^63355681 is an apocalyptic number.

It is an amenable number.

63355681 is a deficient number, since it is larger than the sum of its proper divisors (1).

63355681 is an equidigital number, since it uses as much as digits as its factorization.

63355681 is an evil number, because the sum of its binary digits is even.

The product of its digits is 64800, while the sum is 37.

The square root of 63355681 is about 7959.6281948342. The cubic root of 63355681 is about 398.6531387521.

The spelling of 63355681 in words is "sixty-three million, three hundred fifty-five thousand, six hundred eighty-one".