221676840 has 288 divisors, whose sum is σ = 906272640. Its totient is φ = 45999360.

The previous prime is 221676827. The next prime is 221676853. The reversal of 221676840 is 48676122.

It is an interprime number because it is at equal distance from previous prime (221676827) and next prime (221676853).

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 = 221676795 and 221676804.

It is an unprimeable number.

It is a polite number, since it can be written in 71 ways as a sum of consecutive naturals, for example, 304557 + ... + 305283.

It is an arithmetic number, because the mean of its divisors is an integer number (3146780).

Almost surely, 2^221676840 is an apocalyptic number.

221676840 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 221676840, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (453136320).

221676840 is an abundant number, since it is smaller than the sum of its proper divisors (684595800).

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

221676840 is a wasteful number, since it uses less digits than its factorization.

221676840 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 773 (or 755 counting only the distinct ones).

The product of its (nonzero) digits is 32256, while the sum is 36.

The square root of 221676840 is about 14888.8159368030. The cubic root of 221676840 is about 605.2109457246.

The spelling of 221676840 in words is "two hundred twenty-one million, six hundred seventy-six thousand, eight hundred forty".