221668887 has 32 divisors (see below), whose sum is σ = 335937024. Its totient is φ = 128822400.

The previous prime is 221668883. The next prime is 221668921. The reversal of 221668887 is 788866122.

It is not a de Polignac number, because 221668887 - 2² = 221668883 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (221668883) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 85413 + ... + 87969.

It is an arithmetic number, because the mean of its divisors is an integer number (10498032).

Almost surely, 2^221668887 is an apocalyptic number.

221668887 is a deficient number, since it is larger than the sum of its proper divisors (114268137).

221668887 is a wasteful number, since it uses less digits than its factorization.

221668887 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2679.

The product of its digits is 516096, while the sum is 48.

The square root of 221668887 is about 14888.5488547407. The cubic root of 221668887 is about 605.2037080114.

The spelling of 221668887 in words is "two hundred twenty-one million, six hundred sixty-eight thousand, eight hundred eighty-seven".