22783781 has 2 divisors, whose sum is σ = 22783782. Its totient is φ = 22783780.

The previous prime is 22783771. The next prime is 22783801. The reversal of 22783781 is 18738722.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 22372900 + 410881 = 4730^2 + 641^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-22783781 is a prime.

It is a super-2 number, since 2×22783781² = 1038201353311922, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (22783721) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 11391890 + 11391891.

It is an arithmetic number, because the mean of its divisors is an integer number (11391891).

Almost surely, 2^22783781 is an apocalyptic number.

It is an amenable number.

22783781 is a deficient number, since it is larger than the sum of its proper divisors (1).

22783781 is an equidigital number, since it uses as much as digits as its factorization.

22783781 is an evil number, because the sum of its binary digits is even.

The product of its digits is 37632, while the sum is 38.

The square root of 22783781 is about 4773.2359044992. The cubic root of 22783781 is about 283.4927341427.

The spelling of 22783781 in words is "twenty-two million, seven hundred eighty-three thousand, seven hundred eighty-one".