26820697129 has 4 divisors (see below), whose sum is σ = 26821132884. Its totient is φ = 26820261376.

The previous prime is 26820697109. The next prime is 26820697151. The reversal of 26820697129 is 92179602862.

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 11654282025 + 15166415104 = 107955^2 + 123152^2 .

It is a cyclic number.

It is not a de Polignac number, because 26820697129 - 2¹¹ = 26820695081 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (26820697109) 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, 106612 + ... + 254965.

It is an arithmetic number, because the mean of its divisors is an integer number (6705283221).

Almost surely, 2^26820697129 is an apocalyptic number.

It is an amenable number.

26820697129 is a deficient number, since it is larger than the sum of its proper divisors (435755).

26820697129 is an equidigital number, since it uses as much as digits as its factorization.

26820697129 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 435754.

The product of its (nonzero) digits is 1306368, while the sum is 52.

The spelling of 26820697129 in words is "twenty-six billion, eight hundred twenty million, six hundred ninety-seven thousand, one hundred twenty-nine".