21747791753 has 2 divisors, whose sum is σ = 21747791754. Its totient is φ = 21747791752.

The previous prime is 21747791743. The next prime is 21747791803. The reversal of 21747791753 is 35719774712.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 21214505104 + 533286649 = 145652^2 + 23093^2 .

It is a cyclic number.

It is not a de Polignac number, because 21747791753 - 2¹⁴ = 21747775369 is a prime.

It is a super-4 number, since 4×21747791753⁴ (a number of 42 digits) contains 4444 as substring. Note that it is a super-d number also for d = 2.

It is a junction number, because it is equal to n+sod(n) for n = 21747791695 and 21747791704.

It is not a weakly prime, because it can be changed into another prime (21747791743) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10873895876 + 10873895877.

It is an arithmetic number, because the mean of its divisors is an integer number (10873895877).

Almost surely, 2^21747791753 is an apocalyptic number.

It is an amenable number.

21747791753 is a deficient number, since it is larger than the sum of its proper divisors (1).

21747791753 is an equidigital number, since it uses as much as digits as its factorization.

21747791753 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 2593080, while the sum is 53.

The spelling of 21747791753 in words is "twenty-one billion, seven hundred forty-seven million, seven hundred ninety-one thousand, seven hundred fifty-three".