221856402 has 16 divisors (see below), whose sum is σ = 451234080. Its totient is φ = 72698592.

The previous prime is 221856389. The next prime is 221856419. The reversal of 221856402 is 204658122.

It is a self number, because there is not a number n which added to its sum of digits gives 221856402.

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, 313003 + ... + 313710.

It is an arithmetic number, because the mean of its divisors is an integer number (28202130).

Almost surely, 2^221856402 is an apocalyptic number.

221856402 is an abundant number, since it is smaller than the sum of its proper divisors (229377678).

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

221856402 is a wasteful number, since it uses less digits than its factorization.

221856402 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 626777.

The product of its (nonzero) digits is 7680, while the sum is 30.

The square root of 221856402 is about 14894.8448128874. The cubic root of 221856402 is about 605.3743119995.

The spelling of 221856402 in words is "two hundred twenty-one million, eight hundred fifty-six thousand, four hundred two".