221012399 has 2 divisors, whose sum is σ = 221012400. Its totient is φ = 221012398.

The previous prime is 221012387. The next prime is 221012413. The reversal of 221012399 is 993210122.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 221012399 - 2²⁰ = 219963823 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (221012329) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 110506199 + 110506200.

It is an arithmetic number, because the mean of its divisors is an integer number (110506200).

Almost surely, 2^221012399 is an apocalyptic number.

221012399 is a deficient number, since it is larger than the sum of its proper divisors (1).

221012399 is an equidigital number, since it uses as much as digits as its factorization.

221012399 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 1944, while the sum is 29.

The square root of 221012399 is about 14866.4857649681. The cubic root of 221012399 is about 604.6056661250.

The spelling of 221012399 in words is "two hundred twenty-one million, twelve thousand, three hundred ninety-nine".