22102781 has 2 divisors, whose sum is σ = 22102782. Its totient is φ = 22102780.

The previous prime is 22102733. The next prime is 22102799. The reversal of 22102781 is 18720122.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 19882681 + 2220100 = 4459^2 + 1490^2 .

It is a cyclic number.

It is not a de Polignac number, because 22102781 - 2¹⁰ = 22101757 is a prime.

It is a super-2 number, since 2×22102781² = 977065855867922, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (22107781) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 11051390 + 11051391.

It is an arithmetic number, because the mean of its divisors is an integer number (11051391).

Almost surely, 2^22102781 is an apocalyptic number.

It is an amenable number.

22102781 is a deficient number, since it is larger than the sum of its proper divisors (1).

22102781 is an equidigital number, since it uses as much as digits as its factorization.

22102781 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 448, while the sum is 23.

The square root of 22102781 is about 4701.3594842343. The cubic root of 22102781 is about 280.6396134770.

The spelling of 22102781 in words is "twenty-two million, one hundred two thousand, seven hundred eighty-one".