63940003021 has 2 divisors, whose sum is σ = 63940003022. Its totient is φ = 63940003020.

The previous prime is 63940003019. The next prime is 63940003027. The reversal of 63940003021 is 12030004936.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 44854580521 + 19085422500 = 211789^2 + 138150^2 .

It is a cyclic number.

It is not a de Polignac number, because 63940003021 - 2¹ = 63940003019 is a prime.

Together with 63940003019, it forms a pair of twin primes.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (63940003027) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 31970001510 + 31970001511.

It is an arithmetic number, because the mean of its divisors is an integer number (31970001511).

Almost surely, 2^63940003021 is an apocalyptic number.

It is an amenable number.

63940003021 is a deficient number, since it is larger than the sum of its proper divisors (1).

63940003021 is an equidigital number, since it uses as much as digits as its factorization.

63940003021 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 3888, while the sum is 28.

Adding to 63940003021 its reverse (12030004936), we get a palindrome (75970007957).

The spelling of 63940003021 in words is "sixty-three billion, nine hundred forty million, three thousand, twenty-one".