63521993 has 2 divisors, whose sum is σ = 63521994. Its totient is φ = 63521992.

The previous prime is 63521981. The next prime is 63522029. The reversal of 63521993 is 39912536.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 59413264 + 4108729 = 7708^2 + 2027^2 .

It is a cyclic number.

It is not a de Polignac number, because 63521993 - 2⁸ = 63521737 is a prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (63521893) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 31760996 + 31760997.

It is an arithmetic number, because the mean of its divisors is an integer number (31760997).

Almost surely, 2^63521993 is an apocalyptic number.

It is an amenable number.

63521993 is a deficient number, since it is larger than the sum of its proper divisors (1).

63521993 is an equidigital number, since it uses as much as digits as its factorization.

63521993 is an evil number, because the sum of its binary digits is even.

The product of its digits is 43740, while the sum is 38.

The square root of 63521993 is about 7970.0685693412. The cubic root of 63521993 is about 399.0016624617.

The spelling of 63521993 in words is "sixty-three million, five hundred twenty-one thousand, nine hundred ninety-three".