221725000 has 144 divisors (see below), whose sum is σ = 607812660. Its totient is φ = 75600000.

The previous prime is 221724961. The next prime is 221725013. The reversal of 221725000 is 527122.

It can be written as a sum of positive squares in 6 ways, for example, as 90897156 + 130827844 = 9534^2 + 11438^2 .

It is an unprimeable number.

It is a polite number, since it can be written in 35 ways as a sum of consecutive naturals, for example, 1224910 + ... + 1225090.

Almost surely, 2^221725000 is an apocalyptic number.

221725000 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 221725000, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (303906330).

221725000 is an abundant number, since it is smaller than the sum of its proper divisors (386087660).

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

221725000 is an equidigital number, since it uses as much as digits as its factorization.

221725000 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 226 (or 195 counting only the distinct ones).

The product of its (nonzero) digits is 280, while the sum is 19.

The square root of 221725000 is about 14890.4331703279. The cubic root of 221725000 is about 605.2547705534.

It can be divided in two parts, 22172 and 5000, that added together give a palindrome (27172).

The spelling of 221725000 in words is "two hundred twenty-one million, seven hundred twenty-five thousand".