63437681 has 2 divisors, whose sum is σ = 63437682. Its totient is φ = 63437680.

The previous prime is 63437669. The next prime is 63437683. The reversal of 63437681 is 18673436.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 62094400 + 1343281 = 7880^2 + 1159^2 .

It is a cyclic number.

It is not a de Polignac number, because 63437681 - 2⁶ = 63437617 is a prime.

It is a super-2 number, since 2×63437681² = 8048678741315522, which contains 22 as substring.

It is a Sophie Germain prime.

Together with 63437683, it forms a pair of twin primes.

It is a Chen prime.

It is a Curzon number.

It is not a weakly prime, because it can be changed into another prime (63437683) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 31718840 + 31718841.

It is an arithmetic number, because the mean of its divisors is an integer number (31718841).

Almost surely, 2^63437681 is an apocalyptic number.

It is an amenable number.

63437681 is a deficient number, since it is larger than the sum of its proper divisors (1).

63437681 is an equidigital number, since it uses as much as digits as its factorization.

63437681 is an evil number, because the sum of its binary digits is even.

The product of its digits is 72576, while the sum is 38.

The square root of 63437681 is about 7964.7775235721. Note that the first 3 decimals coincide. The cubic root of 63437681 is about 398.8250542185.

The spelling of 63437681 in words is "sixty-three million, four hundred thirty-seven thousand, six hundred eighty-one".