221494840 has 32 divisors (see below), whose sum is σ = 569558880. Its totient is φ = 75940992.

The previous prime is 221494829. The next prime is 221494859. The reversal of 221494840 is 48494122.

221494840 is digitally balanced in base 3, because in such base it contains all the possibile digits an equal number of times.

It is a junction number, because it is equal to n+sod(n) for n = 221494796 and 221494805.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 395247 + ... + 395806.

It is an arithmetic number, because the mean of its divisors is an integer number (17798715).

Almost surely, 2^221494840 is an apocalyptic number.

221494840 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

221494840 is an abundant number, since it is smaller than the sum of its proper divisors (348064040).

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

221494840 is a wasteful number, since it uses less digits than its factorization.

221494840 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 791071 (or 791067 counting only the distinct ones).

The product of its (nonzero) digits is 18432, while the sum is 34.

The square root of 221494840 is about 14882.7027115373. The cubic root of 221494840 is about 605.0452712976.

The spelling of 221494840 in words is "two hundred twenty-one million, four hundred ninety-four thousand, eight hundred forty".