26809931987 has 2 divisors, whose sum is σ = 26809931988. Its totient is φ = 26809931986.

The previous prime is 26809931917. The next prime is 26809932043. The reversal of 26809931987 is 78913990862.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 26809931987 - 2³² = 22514964691 is a prime.

It is not a weakly prime, because it can be changed into another prime (26809931917) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 13404965993 + 13404965994.

It is an arithmetic number, because the mean of its divisors is an integer number (13404965994).

Almost surely, 2^26809931987 is an apocalyptic number.

26809931987 is a deficient number, since it is larger than the sum of its proper divisors (1).

26809931987 is an equidigital number, since it uses as much as digits as its factorization.

26809931987 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 11757312, while the sum is 62.

The spelling of 26809931987 in words is "twenty-six billion, eight hundred nine million, nine hundred thirty-one thousand, nine hundred eighty-seven".