663221400 has 96 divisors (see below), whose sum is σ = 2075053200. Its totient is φ = 175219200.

The previous prime is 663221381. The next prime is 663221423. The reversal of 663221400 is 4122366.

It is a Harshad number since it is a multiple of its sum of digits (24).

It is a congruent number.

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, 60330 + ... + 70470.

Almost surely, 2^663221400 is an apocalyptic number.

663221400 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 663221400, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1037526600).

663221400 is an abundant number, since it is smaller than the sum of its proper divisors (1411831800).

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

663221400 is a wasteful number, since it uses less digits than its factorization.

663221400 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10269 (or 10260 counting only the distinct ones).

The product of its (nonzero) digits is 1728, while the sum is 24.

The square root of 663221400 is about 25753.0852520625. The cubic root of 663221400 is about 872.0730061200.

Adding to 663221400 its reverse (4122366), we get a palindrome (667343766).

The spelling of 663221400 in words is "six hundred sixty-three million, two hundred twenty-one thousand, four hundred".