221898240 has 120 divisors (see below), whose sum is σ = 768575808. Its totient is φ = 59166720.

The previous prime is 221898223. The next prime is 221898241. The reversal of 221898240 is 42898122.

It is a tau number, because it is divible by the number of its divisors (120).

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a junction number, because it is equal to n+sod(n) for n = 221898195 and 221898204.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (221898241) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 18225 + ... + 27855.

Almost surely, 2^221898240 is an apocalyptic number.

221898240 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 221898240, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (384287904).

221898240 is an abundant number, since it is smaller than the sum of its proper divisors (546677568).

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

221898240 is an equidigital number, since it uses as much as digits as its factorization.

221898240 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9660 (or 9641 counting only the distinct ones).

The product of its (nonzero) digits is 18432, while the sum is 36.

The square root of 221898240 is about 14896.2491923303. The cubic root of 221898240 is about 605.4123637277.

The spelling of 221898240 in words is "two hundred twenty-one million, eight hundred ninety-eight thousand, two hundred forty".