221237983 has 4 divisors (see below), whose sum is σ = 234252000. Its totient is φ = 208223968.

The previous prime is 221237971. The next prime is 221237993. The reversal of 221237983 is 389732122.

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

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-221237983 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 (221237993) 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 in 3 ways as a sum of consecutive naturals, for example, 6506983 + ... + 6507016.

It is an arithmetic number, because the mean of its divisors is an integer number (58563000).

Almost surely, 2^221237983 is an apocalyptic number.

221237983 is a deficient number, since it is larger than the sum of its proper divisors (13014017).

221237983 is a wasteful number, since it uses less digits than its factorization.

221237983 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 13014016.

The product of its digits is 36288, while the sum is 37.

The square root of 221237983 is about 14874.0708281223. The cubic root of 221237983 is about 604.8113001196.

The spelling of 221237983 in words is "two hundred twenty-one million, two hundred thirty-seven thousand, nine hundred eighty-three".