21117677 has 12 divisors (see below), whose sum is σ = 24640416. Its totient is φ = 18045720.

The previous prime is 21117671. The next prime is 21117697. The reversal of 21117677 is 77671112.

It is a happy number.

It is not a de Polignac number, because 21117677 - 2¹⁰ = 21116653 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21117671) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 30578 + ... + 31260.

It is an arithmetic number, because the mean of its divisors is an integer number (2053368).

Almost surely, 2^21117677 is an apocalyptic number.

It is an amenable number.

21117677 is a deficient number, since it is larger than the sum of its proper divisors (3522739).

21117677 is an equidigital number, since it uses as much as digits as its factorization.

21117677 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1328 (or 1321 counting only the distinct ones).

The product of its digits is 4116, while the sum is 32.

The square root of 21117677 is about 4595.3973712836. The cubic root of 21117677 is about 276.4067944140.

Adding to 21117677 its reverse (77671112), we get a palindrome (98788789).

The spelling of 21117677 in words is "twenty-one million, one hundred seventeen thousand, six hundred seventy-seven".