21104255577049 has 2 divisors, whose sum is σ = 21104255577050. Its totient is φ = 21104255577048.

The previous prime is 21104255577019. The next prime is 21104255577107. The reversal of 21104255577049 is 94077555240112.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 13432906698649 + 7671348878400 = 3665093^2 + 2769720^2 .

It is a cyclic number.

It is not a de Polignac number, because 21104255577049 - 2²³ = 21104247188441 is a prime.

It is a super-2 number, since 2×21104255577049² (a number of 27 digits) contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 21104255576987 and 21104255577005.

It is not a weakly prime, because it can be changed into another prime (21104255577019) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10552127788524 + 10552127788525.

It is an arithmetic number, because the mean of its divisors is an integer number (10552127788525).

Almost surely, 2^{21104255577049} is an apocalyptic number.

It is an amenable number.

21104255577049 is a deficient number, since it is larger than the sum of its proper divisors (1).

21104255577049 is an equidigital number, since it uses as much as digits as its factorization.

21104255577049 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 3528000, while the sum is 52.

The spelling of 21104255577049 in words is "twenty-one trillion, one hundred four billion, two hundred fifty-five million, five hundred seventy-seven thousand, forty-nine".