21106753757 has 2 divisors, whose sum is σ = 21106753758. Its totient is φ = 21106753756.

The previous prime is 21106753741. The next prime is 21106753769. The reversal of 21106753757 is 75735760112.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 18294997081 + 2811756676 = 135259^2 + 53026^2 .

It is a cyclic number.

It is not a de Polignac number, because 21106753757 - 2⁴ = 21106753741 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21106750757) 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 as a sum of consecutive naturals, namely, 10553376878 + 10553376879.

It is an arithmetic number, because the mean of its divisors is an integer number (10553376879).

Almost surely, 2^21106753757 is an apocalyptic number.

It is an amenable number.

21106753757 is a deficient number, since it is larger than the sum of its proper divisors (1).

21106753757 is an equidigital number, since it uses as much as digits as its factorization.

21106753757 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 308700, while the sum is 44.

The spelling of 21106753757 in words is "twenty-one billion, one hundred six million, seven hundred fifty-three thousand, seven hundred fifty-seven".