221979671 has 8 divisors (see below), whose sum is σ = 226363488. Its totient is φ = 217620000.

The previous prime is 221979661. The next prime is 221979673. The reversal of 221979671 is 176979122.

221979671 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-221979671 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (221979673) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 13121 + ... + 24821.

It is an arithmetic number, because the mean of its divisors is an integer number (28295436).

Almost surely, 2^221979671 is an apocalyptic number.

221979671 is a deficient number, since it is larger than the sum of its proper divisors (4383817).

221979671 is a wasteful number, since it uses less digits than its factorization.

221979671 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 12073.

The product of its digits is 95256, while the sum is 44.

The square root of 221979671 is about 14898.9822135608. The cubic root of 221979671 is about 605.4864116410.

The spelling of 221979671 in words is "two hundred twenty-one million, nine hundred seventy-nine thousand, six hundred seventy-one".