22713781 has 2 divisors, whose sum is σ = 22713782. Its totient is φ = 22713780.

The previous prime is 22713773. The next prime is 22713787. The reversal of 22713781 is 18731722.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 21252100 + 1461681 = 4610^2 + 1209^2 .

It is a cyclic number.

It is not a de Polignac number, because 22713781 - 2³ = 22713773 is a prime.

It is a super-2 number, since 2×22713781² = 1031831694631922, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (22713787) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 11356890 + 11356891.

It is an arithmetic number, because the mean of its divisors is an integer number (11356891).

Almost surely, 2^22713781 is an apocalyptic number.

It is an amenable number.

22713781 is a deficient number, since it is larger than the sum of its proper divisors (1).

22713781 is an equidigital number, since it uses as much as digits as its factorization.

22713781 is an evil number, because the sum of its binary digits is even.

The product of its digits is 4704, while the sum is 31.

The square root of 22713781 is about 4765.8977118692. The cubic root of 22713781 is about 283.2021056279.

The spelling of 22713781 in words is "twenty-two million, seven hundred thirteen thousand, seven hundred eighty-one".