21707122 has 16 divisors (see below), whose sum is σ = 33697944. Its totient is φ = 10480000.

The previous prime is 21707117. The next prime is 21707137. The reversal of 21707122 is 22170712.

It can be written as a sum of positive squares in 4 ways, for example, as 20802721 + 904401 = 4561^2 + 951^2 .

It is a junction number, because it is equal to n+sod(n) for n = 21707093 and 21707102.

It is an unprimeable number.

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 7 ways as a sum of consecutive naturals, for example, 6972 + ... + 9592.

Almost surely, 2^21707122 is an apocalyptic number.

21707122 is a deficient number, since it is larger than the sum of its proper divisors (11990822).

21707122 is a wasteful number, since it uses less digits than its factorization.

21707122 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2765.

The product of its (nonzero) digits is 392, while the sum is 22.

The square root of 21707122 is about 4659.0902545454. The cubic root of 21707122 is about 278.9549564792.

Adding to 21707122 its reverse (22170712), we get a palindrome (43877834).

The spelling of 21707122 in words is "twenty-one million, seven hundred seven thousand, one hundred twenty-two".