221532791 has 2 divisors, whose sum is σ = 221532792. Its totient is φ = 221532790.

The previous prime is 221532767. The next prime is 221532793. The reversal of 221532791 is 197235122.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 221532791 - 2¹⁰ = 221531767 is a prime.

Together with 221532793, it forms a pair of twin primes.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (221532793) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 110766395 + 110766396.

It is an arithmetic number, because the mean of its divisors is an integer number (110766396).

Almost surely, 2^221532791 is an apocalyptic number.

221532791 is a deficient number, since it is larger than the sum of its proper divisors (1).

221532791 is an equidigital number, since it uses as much as digits as its factorization.

221532791 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 7560, while the sum is 32.

The square root of 221532791 is about 14883.9776605583. The cubic root of 221532791 is about 605.0798255439.

The spelling of 221532791 in words is "two hundred twenty-one million, five hundred thirty-two thousand, seven hundred ninety-one".