21049076791 has 2 divisors, whose sum is σ = 21049076792. Its totient is φ = 21049076790.

The previous prime is 21049076777. The next prime is 21049076827. The reversal of 21049076791 is 19767094012.

It is a weak prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21049076791 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21049076731) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10524538395 + 10524538396.

It is an arithmetic number, because the mean of its divisors is an integer number (10524538396).

Almost surely, 2^21049076791 is an apocalyptic number.

21049076791 is a deficient number, since it is larger than the sum of its proper divisors (1).

21049076791 is an equidigital number, since it uses as much as digits as its factorization.

21049076791 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 190512, while the sum is 46.

The spelling of 21049076791 in words is "twenty-one billion, forty-nine million, seventy-six thousand, seven hundred ninety-one".