221964460 has 72 divisors (see below), whose sum is σ = 500030496. Its totient is φ = 82736640.

The previous prime is 221964451. The next prime is 221964469. The reversal of 221964460 is 64469122.

It is an interprime number because it is at equal distance from previous prime (221964451) and next prime (221964469).

It is not an unprimeable number, because it can be changed into a prime (221964469) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 512404 + ... + 512836.

It is an arithmetic number, because the mean of its divisors is an integer number (6944868).

Almost surely, 2^221964460 is an apocalyptic number.

221964460 is a gapful number since it is divisible by the number (20) 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 221964460, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (250015248).

221964460 is an abundant number, since it is smaller than the sum of its proper divisors (278066036).

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

221964460 is a wasteful number, since it uses less digits than its factorization.

221964460 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 551 (or 530 counting only the distinct ones).

The product of its (nonzero) digits is 20736, while the sum is 34.

The square root of 221964460 is about 14898.4717337048. The cubic root of 221964460 is about 605.4725811490.

The spelling of 221964460 in words is "two hundred twenty-one million, nine hundred sixty-four thousand, four hundred sixty".