21755112517673 has 2 divisors, whose sum is σ = 21755112517674. Its totient is φ = 21755112517672.

The previous prime is 21755112517657. The next prime is 21755112517711. The reversal of 21755112517673 is 37671521155712.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 18472047559744 + 3283064957929 = 4297912^2 + 1811923^2 .

It is a cyclic number.

It is not a de Polignac number, because 21755112517673 - 2⁴ = 21755112517657 is a prime.

It is a super-2 number, since 2×21755112517673² (a number of 27 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (21755112517603) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10877556258836 + 10877556258837.

It is an arithmetic number, because the mean of its divisors is an integer number (10877556258837).

Almost surely, 2^{21755112517673} is an apocalyptic number.

It is an amenable number.

21755112517673 is a deficient number, since it is larger than the sum of its proper divisors (1).

21755112517673 is an equidigital number, since it uses as much as digits as its factorization.

21755112517673 is an evil number, because the sum of its binary digits is even.

The product of its digits is 3087000, while the sum is 53.

The spelling of 21755112517673 in words is "twenty-one trillion, seven hundred fifty-five billion, one hundred twelve million, five hundred seventeen thousand, six hundred seventy-three".