663461220 has 72 divisors (see below), whose sum is σ = 1942065216. Its totient is φ = 169222592.

The previous prime is 663461207. The next prime is 663461231. The reversal of 663461220 is 22164366.

It is a Harshad number since it is a multiple of its sum of digits (30).

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 21289 + ... + 42191.

It is an arithmetic number, because the mean of its divisors is an integer number (26973128).

Almost surely, 2^663461220 is an apocalyptic number.

663461220 is a gapful number since it is divisible by the number (60) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 663461220, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (971032608).

663461220 is an abundant number, since it is smaller than the sum of its proper divisors (1278603996).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

663461220 is a wasteful number, since it uses less digits than its factorization.

663461220 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 20961 (or 20936 counting only the distinct ones).

The product of its (nonzero) digits is 10368, while the sum is 30.

The square root of 663461220 is about 25757.7409723757. The cubic root of 663461220 is about 872.1781069431.

The spelling of 663461220 in words is "six hundred sixty-three million, four hundred sixty-one thousand, two hundred twenty".