221449978 has 16 divisors (see below), whose sum is σ = 353592000. Its totient is φ = 103717152.

The previous prime is 221449967. The next prime is 221449981. The reversal of 221449978 is 879944122.

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, 29358 + ... + 36121.

It is an arithmetic number, because the mean of its divisors is an integer number (22099500).

Almost surely, 2^221449978 is an apocalyptic number.

221449978 is a deficient number, since it is larger than the sum of its proper divisors (132142022).

221449978 is a wasteful number, since it uses less digits than its factorization.

221449978 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 65589.

The product of its digits is 290304, while the sum is 46.

The square root of 221449978 is about 14881.1954492910. The cubic root of 221449978 is about 605.0044195201.

The spelling of 221449978 in words is "two hundred twenty-one million, four hundred forty-nine thousand, nine hundred seventy-eight".