113217821 has 2 divisors, whose sum is σ = 113217822. Its totient is φ = 113217820.

The previous prime is 113217803. The next prime is 113217887. The reversal of 113217821 is 128712311.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 86229796 + 26988025 = 9286^2 + 5195^2 .

It is a cyclic number.

It is not a de Polignac number, because 113217821 - 2⁶ = 113217757 is a prime.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (113210821) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 56608910 + 56608911.

It is an arithmetic number, because the mean of its divisors is an integer number (56608911).

Almost surely, 2^113217821 is an apocalyptic number.

It is an amenable number.

113217821 is a deficient number, since it is larger than the sum of its proper divisors (1).

113217821 is an equidigital number, since it uses as much as digits as its factorization.

113217821 is an evil number, because the sum of its binary digits is even.

The product of its digits is 672, while the sum is 26.

The square root of 113217821 is about 10640.3863181747. The cubic root of 113217821 is about 483.7692548650.

The spelling of 113217821 in words is "one hundred thirteen million, two hundred seventeen thousand, eight hundred twenty-one".