4223981 has 2 divisors, whose sum is σ = 4223982. Its totient is φ = 4223980.

The previous prime is 4223977. The next prime is 4223983. The reversal of 4223981 is 1893224.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 3822025 + 401956 = 1955^2 + 634^2 .

It is a cyclic number.

It is not a de Polignac number, because 4223981 - 2² = 4223977 is a prime.

It is a super-2 number, since 2×4223981² = 35684030976722, which contains 22 as substring.

Together with 4223983, it forms a pair of twin primes.

It is a Chen prime.

It is an Ulam number.

It is a d-powerful number, because it can be written as 4² + 2¹³ + 2¹⁹ + 3¹³ + 9 + 8⁷ + 1 .

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (4223983) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 2111990 + 2111991.

It is an arithmetic number, because the mean of its divisors is an integer number (2111991).

Almost surely, 2^4223981 is an apocalyptic number.

It is an amenable number.

4223981 is a deficient number, since it is larger than the sum of its proper divisors (1).

4223981 is an equidigital number, since it uses as much as digits as its factorization.

4223981 is an evil number, because the sum of its binary digits is even.

The product of its digits is 3456, while the sum is 29.

The square root of 4223981 is about 2055.2325902437. The cubic root of 4223981 is about 161.6493584522.

The spelling of 4223981 in words is "four million, two hundred twenty-three thousand, nine hundred eighty-one".