221870286 has 64 divisors (see below), whose sum is σ = 555264000. Its totient is φ = 65059200.

The previous prime is 221870279. The next prime is 221870303. The reversal of 221870286 is 682078122.

It is a happy number.

It is a self number, because there is not a number n which added to its sum of digits gives 221870286.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 12390 + ... + 24438.

It is an arithmetic number, because the mean of its divisors is an integer number (8676000).

Almost surely, 2^221870286 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 221870286, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (277632000).

221870286 is an abundant number, since it is smaller than the sum of its proper divisors (333393714).

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

221870286 is a wasteful number, since it uses less digits than its factorization.

221870286 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 12102 (or 12096 counting only the distinct ones).

The product of its (nonzero) digits is 21504, while the sum is 36.

The square root of 221870286 is about 14895.3108728888. The cubic root of 221870286 is about 605.3869400501.

The spelling of 221870286 in words is "two hundred twenty-one million, eight hundred seventy thousand, two hundred eighty-six".