221689988 has 24 divisors (see below), whose sum is σ = 420819840. Its totient is φ = 101579040.

The previous prime is 221689973. The next prime is 221690003. The reversal of 221689988 is 889986122.

It is an interprime number because it is at equal distance from previous prime (221689973) and next prime (221690003).

It is an unprimeable number.

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 7 ways as a sum of consecutive naturals, for example, 8108 + ... + 22563.

It is an arithmetic number, because the mean of its divisors is an integer number (17534160).

Almost surely, 2^221689988 is an apocalyptic number.

It is an amenable number.

221689988 is a deficient number, since it is larger than the sum of its proper divisors (199129852).

221689988 is a wasteful number, since it uses less digits than its factorization.

221689988 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 30827 (or 30825 counting only the distinct ones).

The product of its digits is 995328, while the sum is 53.

The square root of 221689988 is about 14889.2574697330. The cubic root of 221689988 is about 605.2229108239. Note that the first 3 decimals are identical.

The spelling of 221689988 in words is "two hundred twenty-one million, six hundred eighty-nine thousand, nine hundred eighty-eight".