21177713 has 2 divisors, whose sum is σ = 21177714. Its totient is φ = 21177712.

The previous prime is 21177707. The next prime is 21177731. The reversal of 21177713 is 31777112.

Together with next prime (21177731) it forms an Ormiston pair, because they use the same digits, order apart.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 11242609 + 9935104 = 3353^2 + 3152^2 .

It is a cyclic number.

It is not a de Polignac number, because 21177713 - 2⁶ = 21177649 is a prime.

It is not a weakly prime, because it can be changed into another prime (21177703) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10588856 + 10588857.

It is an arithmetic number, because the mean of its divisors is an integer number (10588857).

Almost surely, 2^21177713 is an apocalyptic number.

It is an amenable number.

21177713 is a deficient number, since it is larger than the sum of its proper divisors (1).

21177713 is an equidigital number, since it uses as much as digits as its factorization.

21177713 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 2058, while the sum is 29.

The square root of 21177713 is about 4601.9249233337. The cubic root of 21177713 is about 276.6684813029.

The spelling of 21177713 in words is "twenty-one million, one hundred seventy-seven thousand, seven hundred thirteen".