221392990 has 64 divisors (see below), whose sum is σ = 495040896. Its totient is φ = 69414912.

The previous prime is 221392967. The next prime is 221392993. The reversal of 221392990 is 99293122.

221392990 is digitally balanced in base 3, because in such base it contains all the possibile digits an equal number of times.

It is a super-2 number, since 2×221392990² = 98029712042280200, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (221392993) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 101754 + ... + 103906.

It is an arithmetic number, because the mean of its divisors is an integer number (7735014).

Almost surely, 2^221392990 is an apocalyptic number.

221392990 is an abundant number, since it is smaller than the sum of its proper divisors (273647906).

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

221392990 is a wasteful number, since it uses less digits than its factorization.

221392990 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2293.

The product of its (nonzero) digits is 17496, while the sum is 37.

The square root of 221392990 is about 14879.2805605647. The cubic root of 221392990 is about 604.9525177315.

The spelling of 221392990 in words is "two hundred twenty-one million, three hundred ninety-two thousand, nine hundred ninety".