63904921 has 8 divisors (see below), whose sum is σ = 67737600. Its totient is φ = 60080448.

The previous prime is 63904901. The next prime is 63904927. The reversal of 63904921 is 12940936.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 63904921 - 2⁵ = 63904889 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (63904927) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 22440 + ... + 25126.

It is an arithmetic number, because the mean of its divisors is an integer number (8467200).

Almost surely, 2^63904921 is an apocalyptic number.

It is an amenable number.

63904921 is a deficient number, since it is larger than the sum of its proper divisors (3832679).

63904921 is a wasteful number, since it uses less digits than its factorization.

63904921 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4103.

The product of its (nonzero) digits is 11664, while the sum is 34.

The square root of 63904921 is about 7994.0553538239. The cubic root of 63904921 is about 399.8018205785.

It can be divided in two parts, 6390 and 4921, that added together give a palindrome (11311).

The spelling of 63904921 in words is "sixty-three million, nine hundred four thousand, nine hundred twenty-one".