221040989 has 4 divisors (see below), whose sum is σ = 238044156. Its totient is φ = 204037824.

The previous prime is 221040979. The next prime is 221041019. The reversal of 221040989 is 989040122.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 98208100 + 122832889 = 9910^2 + 11083^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-221040989 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (221040959) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 8501564 + ... + 8501589.

It is an arithmetic number, because the mean of its divisors is an integer number (59511039).

Almost surely, 2^221040989 is an apocalyptic number.

It is an amenable number.

221040989 is a deficient number, since it is larger than the sum of its proper divisors (17003167).

221040989 is a wasteful number, since it uses less digits than its factorization.

221040989 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 17003166.

The product of its (nonzero) digits is 10368, while the sum is 35.

The square root of 221040989 is about 14867.4472926592. The cubic root of 221040989 is about 604.6317354478.

The spelling of 221040989 in words is "two hundred twenty-one million, forty thousand, nine hundred eighty-nine".