22773781 has 2 divisors, whose sum is σ = 22773782. Its totient is φ = 22773780.

The previous prime is 22773743. The next prime is 22773797. The reversal of 22773781 is 18737722.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 17056900 + 5716881 = 4130^2 + 2391^2 .

It is a cyclic number.

It is not a de Polignac number, because 22773781 - 2¹¹ = 22771733 is a prime.

It is a super-2 number, since 2×22773781² = 1037290202071922, which contains 22 as substring.

It is a nialpdrome in base 12.

It is a self number, because there is not a number n which added to its sum of digits gives 22773781.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (22773701) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 11386890 + 11386891.

It is an arithmetic number, because the mean of its divisors is an integer number (11386891).

Almost surely, 2^22773781 is an apocalyptic number.

It is an amenable number.

22773781 is a deficient number, since it is larger than the sum of its proper divisors (1).

22773781 is an equidigital number, since it uses as much as digits as its factorization.

22773781 is an evil number, because the sum of its binary digits is even.

The product of its digits is 32928, while the sum is 37.

The square root of 22773781 is about 4772.1882821196. The cubic root of 22773781 is about 283.4512522628.

The spelling of 22773781 in words is "twenty-two million, seven hundred seventy-three thousand, seven hundred eighty-one".