221951000279 has 2 divisors, whose sum is σ = 221951000280. Its totient is φ = 221951000278.

The previous prime is 221951000263. The next prime is 221951000309. The reversal of 221951000279 is 972000159122.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 221951000279 - 2⁴ = 221951000263 is a prime.

It is a Sophie Germain prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (221951002279) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 110975500139 + 110975500140.

It is an arithmetic number, because the mean of its divisors is an integer number (110975500140).

Almost surely, 2^221951000279 is an apocalyptic number.

221951000279 is a deficient number, since it is larger than the sum of its proper divisors (1).

221951000279 is an equidigital number, since it uses as much as digits as its factorization.

221951000279 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 22680, while the sum is 38.

The spelling of 221951000279 in words is "two hundred twenty-one billion, nine hundred fifty-one million, two hundred seventy-nine", and thus it is an aban number.