22180681 has 4 divisors (see below), whose sum is σ = 22202500. Its totient is φ = 22158864.

The previous prime is 22180661. The next prime is 22180687. The reversal of 22180681 is 18608122.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 4372281 + 17808400 = 2091^2 + 4220^2 .

It is a cyclic number.

It is not a de Polignac number, because 22180681 - 2¹¹ = 22178633 is a prime.

It is a super-2 number, since 2×22180681² = 983965219247522, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (22180687) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 9306 + ... + 11443.

It is an arithmetic number, because the mean of its divisors is an integer number (5550625).

Almost surely, 2^22180681 is an apocalyptic number.

It is an amenable number.

22180681 is a deficient number, since it is larger than the sum of its proper divisors (21819).

22180681 is a wasteful number, since it uses less digits than its factorization.

22180681 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 21818.

The product of its (nonzero) digits is 1536, while the sum is 28.

The square root of 22180681 is about 4709.6370348467. The cubic root of 22180681 is about 280.9689263732.

The spelling of 22180681 in words is "twenty-two million, one hundred eighty thousand, six hundred eighty-one".