221993479 has 2 divisors, whose sum is σ = 221993480. Its totient is φ = 221993478.

The previous prime is 221993437. The next prime is 221993483. The reversal of 221993479 is 974399122.

It is a happy number.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 221993479 - 2⁷ = 221993351 is a prime.

It is a super-2 number, since 2×221993479² = 98562209437046882, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (221993419) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 110996739 + 110996740.

It is an arithmetic number, because the mean of its divisors is an integer number (110996740).

Almost surely, 2^221993479 is an apocalyptic number.

221993479 is a deficient number, since it is larger than the sum of its proper divisors (1).

221993479 is an equidigital number, since it uses as much as digits as its factorization.

221993479 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 244944, while the sum is 46.

The square root of 221993479 is about 14899.4455937125. The cubic root of 221993479 is about 605.4989659183.

The spelling of 221993479 in words is "two hundred twenty-one million, nine hundred ninety-three thousand, four hundred seventy-nine".