221982640 has 40 divisors (see below), whose sum is σ = 563030928. Its totient is φ = 80720640.

The previous prime is 221982623. The next prime is 221982659. The reversal of 221982640 is 46289122.

It is a tau number, because it is divible by the number of its divisors (40).

It is a super-2 number, since 2×221982640² = 98552584922739200, which contains 22 as substring.

It is a Smith number, since the sum of its digits (34) coincides with the sum of the digits of its prime factors.

It is a junction number, because it is equal to n+sod(n) for n = 221982596 and 221982605.

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, 125247 + ... + 127006.

Almost surely, 2^221982640 is an apocalyptic number.

221982640 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

221982640 is an abundant number, since it is smaller than the sum of its proper divisors (341048288).

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

221982640 is a wasteful number, since it uses less digits than its factorization.

221982640 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 252277 (or 252271 counting only the distinct ones).

The product of its (nonzero) digits is 13824, while the sum is 34.

The square root of 221982640 is about 14899.0818509061. The cubic root of 221982640 is about 605.4891111091.

The spelling of 221982640 in words is "two hundred twenty-one million, nine hundred eighty-two thousand, six hundred forty".