664221963 has 16 divisors (see below), whose sum is σ = 900218880. Its totient is φ = 435553344.

The previous prime is 664221949. The next prime is 664221973. The reversal of 664221963 is 369122466.

It is not a de Polignac number, because 664221963 - 2⁸ = 664221707 is a prime.

It is a super-2 number, since 2×664221963² = 882381632263146738, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (664221913) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 79918 + ... + 87836.

It is an arithmetic number, because the mean of its divisors is an integer number (56263680).

Almost surely, 2^664221963 is an apocalyptic number.

664221963 is a deficient number, since it is larger than the sum of its proper divisors (235996917).

664221963 is a wasteful number, since it uses less digits than its factorization.

664221963 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8378.

The product of its digits is 93312, while the sum is 39.

The square root of 664221963 is about 25772.5040110580. The cubic root of 664221963 is about 872.5113341330.

The spelling of 664221963 in words is "six hundred sixty-four million, two hundred twenty-one thousand, nine hundred sixty-three".