221520000 has 320 divisors, whose sum is σ = 802992960. Its totient is φ = 53760000.

The previous prime is 221519983. The next prime is 221520001. The reversal of 221520000 is 25122.

It is a tau number, because it is divible by the number of its divisors (320).

It is a super-2 number, since 2×221520000² = 98142220800000000, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (12).

It is not an unprimeable number, because it can be changed into a prime (221520001) by changing a digit.

It is a polite number, since it can be written in 39 ways as a sum of consecutive naturals, for example, 3119965 + ... + 3120035.

It is an arithmetic number, because the mean of its divisors is an integer number (2509353).

Almost surely, 2^221520000 is an apocalyptic number.

221520000 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 221520000, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (401496480).

221520000 is an abundant number, since it is smaller than the sum of its proper divisors (581472960).

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

221520000 is an equidigital number, since it uses as much as digits as its factorization.

221520000 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 121 (or 94 counting only the distinct ones).

The product of its (nonzero) digits is 40, while the sum is 12.

The square root of 221520000 is about 14883.5479641112. The cubic root of 221520000 is about 605.0681798262.

Adding to 221520000 its reverse (25122), we get a palindrome (221545122).

The spelling of 221520000 in words is "two hundred twenty-one million, five hundred twenty thousand".