26143681 has 4 divisors (see below), whose sum is σ = 26637012. Its totient is φ = 25650352.

The previous prime is 26143669. The next prime is 26143697. The reversal of 26143681 is 18634162.

26143681 = 3615² + 3616².

It is a happy number.

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 13075456 + 13068225 = 3616^2 + 3615^2 .

It is a cyclic number.

It is not a de Polignac number, because 26143681 - 2⁷ = 26143553 is a prime.

It is a super-2 number, since 2×26143681² = 1366984112459522, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (26143651) 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, 246586 + ... + 246691.

It is an arithmetic number, because the mean of its divisors is an integer number (6659253).

Almost surely, 2^26143681 is an apocalyptic number.

26143681 is the 3616-th centered square number.

It is an amenable number.

26143681 is a deficient number, since it is larger than the sum of its proper divisors (493331).

26143681 is an equidigital number, since it uses as much as digits as its factorization.

26143681 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 493330.

The product of its digits is 6912, while the sum is 31.

The square root of 26143681 is about 5113.0891836540. The cubic root of 26143681 is about 296.7943154475.

The spelling of 26143681 in words is "twenty-six million, one hundred forty-three thousand, six hundred eighty-one".