63489721 has 4 divisors (see below), whose sum is σ = 63557712. Its totient is φ = 63421732.

The previous prime is 63489709. The next prime is 63489733. The reversal of 63489721 is 12798436.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is an interprime number because it is at equal distance from previous prime (63489709) and next prime (63489733).

It is a cyclic number.

It is not a de Polignac number, because 63489721 - 2²³ = 55101113 is a prime.

It is a Smith number, since the sum of its digits (40) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (63489791) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 32575 + ... + 34468.

It is an arithmetic number, because the mean of its divisors is an integer number (15889428).

Almost surely, 2^63489721 is an apocalyptic number.

It is an amenable number.

63489721 is a deficient number, since it is larger than the sum of its proper divisors (67991).

63489721 is an equidigital number, since it uses as much as digits as its factorization.

63489721 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 67990.

The product of its digits is 72576, while the sum is 40.

The square root of 63489721 is about 7968.0437373298. The cubic root of 63489721 is about 398.9340808138.

The spelling of 63489721 in words is "sixty-three million, four hundred eighty-nine thousand, seven hundred twenty-one".