221356379 has 2 divisors, whose sum is σ = 221356380. Its totient is φ = 221356378.

The previous prime is 221356361. The next prime is 221356381. The reversal of 221356379 is 973653122.

221356379 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-221356379 is a prime.

Together with 221356381, it forms a pair of twin primes.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (221356309) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 110678189 + 110678190.

It is an arithmetic number, because the mean of its divisors is an integer number (110678190).

Almost surely, 2^221356379 is an apocalyptic number.

221356379 is a deficient number, since it is larger than the sum of its proper divisors (1).

221356379 is an equidigital number, since it uses as much as digits as its factorization.

221356379 is an evil number, because the sum of its binary digits is even.

The product of its digits is 68040, while the sum is 38.

The square root of 221356379 is about 14878.0502418832. The cubic root of 221356379 is about 604.9191695851.

The spelling of 221356379 in words is "two hundred twenty-one million, three hundred fifty-six thousand, three hundred seventy-nine".