26681639 has 2 divisors, whose sum is σ = 26681640. Its totient is φ = 26681638.

The previous prime is 26681621. The next prime is 26681647. The reversal of 26681639 is 93618662.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 26681639 - 2¹⁶ = 26616103 is a prime.

It is a Sophie Germain prime.

It is a junction number, because it is equal to n+sod(n) for n = 26681596 and 26681605.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (26681609) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 13340819 + 13340820.

It is an arithmetic number, because the mean of its divisors is an integer number (13340820).

Almost surely, 2^26681639 is an apocalyptic number.

26681639 is a deficient number, since it is larger than the sum of its proper divisors (1).

26681639 is an equidigital number, since it uses as much as digits as its factorization.

26681639 is an evil number, because the sum of its binary digits is even.

The product of its digits is 93312, while the sum is 41.

The square root of 26681639 is about 5165.4272814550. The cubic root of 26681639 is about 298.8162202139.

The spelling of 26681639 in words is "twenty-six million, six hundred eighty-one thousand, six hundred thirty-nine".