3991223 has 2 divisors, whose sum is σ = 3991224. Its totient is φ = 3991222.

The previous prime is 3991199. The next prime is 3991237. The reversal of 3991223 is 3221993.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 3991223 - 2⁸ = 3990967 is a prime.

It is a super-2 number, since 2×3991223² = 31859722071458, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (3991723) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1995611 + 1995612.

It is an arithmetic number, because the mean of its divisors is an integer number (1995612).

Almost surely, 2^3991223 is an apocalyptic number.

3991223 is a deficient number, since it is larger than the sum of its proper divisors (1).

3991223 is an equidigital number, since it uses as much as digits as its factorization.

3991223 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 2916, while the sum is 29.

The square root of 3991223 is about 1997.8045449943. The cubic root of 3991223 is about 158.6239150133.

The spelling of 3991223 in words is "three million, nine hundred ninety-one thousand, two hundred twenty-three".