26420981391 has 48 divisors (see below), whose sum is σ = 44223379200. Its totient is φ = 14887998720.

The previous prime is 26420981387. The next prime is 26420981393. The reversal of 26420981391 is 19318902462.

26420981391 is a `hidden beast` number, since 2 + 6 + 420 + 98 + 139 + 1 = 666.

It is not a de Polignac number, because 26420981391 - 2² = 26420981387 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (26420981393) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 2981335 + ... + 2990183.

It is an arithmetic number, because the mean of its divisors is an integer number (921320400).

Almost surely, 2^26420981391 is an apocalyptic number.

26420981391 is a gapful number since it is divisible by the number (21) formed by its first and last digit.

26420981391 is a deficient number, since it is larger than the sum of its proper divisors (17802397809).

26420981391 is a wasteful number, since it uses less digits than its factorization.

26420981391 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9516 (or 9513 counting only the distinct ones).

The product of its (nonzero) digits is 186624, while the sum is 45.

The spelling of 26420981391 in words is "twenty-six billion, four hundred twenty million, nine hundred eighty-one thousand, three hundred ninety-one".