63232721 has 2 divisors, whose sum is σ = 63232722. Its totient is φ = 63232720.

The previous prime is 63232717. The next prime is 63232723. The reversal of 63232721 is 12723236.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 44742721 + 18490000 = 6689^2 + 4300^2 .

It is a cyclic number.

It is not a de Polignac number, because 63232721 - 2² = 63232717 is a prime.

Together with 63232723, it forms a pair of twin primes.

It is a Chen prime.

It is an alternating number because its digits alternate between even and odd.

It is not a weakly prime, because it can be changed into another prime (63232723) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 31616360 + 31616361.

It is an arithmetic number, because the mean of its divisors is an integer number (31616361).

Almost surely, 2^63232721 is an apocalyptic number.

It is an amenable number.

63232721 is a deficient number, since it is larger than the sum of its proper divisors (1).

63232721 is an equidigital number, since it uses as much as digits as its factorization.

63232721 is an evil number, because the sum of its binary digits is even.

The product of its digits is 3024, while the sum is 26.

The square root of 63232721 is about 7951.9004646688. The cubic root of 63232721 is about 398.3950712047.

Adding to 63232721 its reverse (12723236), we get a palindrome (75955957).

The spelling of 63232721 in words is "sixty-three million, two hundred thirty-two thousand, seven hundred twenty-one".