221109947 has 2 divisors, whose sum is σ = 221109948. Its totient is φ = 221109946.

The previous prime is 221109943. The next prime is 221110003. The reversal of 221109947 is 749901122.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 221109947 - 2² = 221109943 is a prime.

It is not a weakly prime, because it can be changed into another prime (221109943) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 110554973 + 110554974.

It is an arithmetic number, because the mean of its divisors is an integer number (110554974).

Almost surely, 2^221109947 is an apocalyptic number.

221109947 is a deficient number, since it is larger than the sum of its proper divisors (1).

221109947 is an equidigital number, since it uses as much as digits as its factorization.

221109947 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 9072, while the sum is 35.

The square root of 221109947 is about 14869.7662052905. The cubic root of 221109947 is about 604.6946044212.

The spelling of 221109947 in words is "two hundred twenty-one million, one hundred nine thousand, nine hundred forty-seven".