221222478 has 16 divisors (see below), whose sum is σ = 449698896. Its totient is φ = 72531840.

The previous prime is 221222461. The next prime is 221222497. The reversal of 221222478 is 874222122.

It is a congruent number.

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, 301851 + ... + 302582.

It is an arithmetic number, because the mean of its divisors is an integer number (28106181).

Almost surely, 2^221222478 is an apocalyptic number.

221222478 is an abundant number, since it is smaller than the sum of its proper divisors (228476418).

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

221222478 is a wasteful number, since it uses less digits than its factorization.

221222478 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 604499.

The product of its digits is 7168, while the sum is 30.

The square root of 221222478 is about 14873.5496099620. The cubic root of 221222478 is about 604.7971708124.

The spelling of 221222478 in words is "two hundred twenty-one million, two hundred twenty-two thousand, four hundred seventy-eight".