26680993921 has 4 divisors (see below), whose sum is σ = 26956055812. Its totient is φ = 26405932032.

The previous prime is 26680993873. The next prime is 26680993931. The reversal of 26680993921 is 12939908662.

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 17230237696 + 9450756225 = 131264^2 + 97215^2 .

It is a cyclic number.

It is not a de Polignac number, because 26680993921 - 2²⁹ = 26144123009 is a prime.

It is a super-2 number, since 2×26680993921² (a number of 22 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (26680993931) 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, 137530800 + ... + 137530993.

It is an arithmetic number, because the mean of its divisors is an integer number (6739013953).

Almost surely, 2^26680993921 is an apocalyptic number.

It is an amenable number.

26680993921 is a deficient number, since it is larger than the sum of its proper divisors (275061891).

26680993921 is an equidigital number, since it uses as much as digits as its factorization.

26680993921 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 275061890.

The product of its (nonzero) digits is 2519424, while the sum is 55.

The spelling of 26680993921 in words is "twenty-six billion, six hundred eighty million, nine hundred ninety-three thousand, nine hundred twenty-one".