21706126 has 16 divisors (see below), whose sum is σ = 35200368. Its totient is φ = 9979200.

The previous prime is 21706109. The next prime is 21706133. The reversal of 21706126 is 62160712.

It is a self number, because there is not a number n which added to its sum of digits gives 21706126.

It is a congruent number.

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, 5821 + ... + 8791.

It is an arithmetic number, because the mean of its divisors is an integer number (2200023).

Almost surely, 2^21706126 is an apocalyptic number.

21706126 is a gapful number since it is divisible by the number (26) formed by its first and last digit.

21706126 is a deficient number, since it is larger than the sum of its proper divisors (13494242).

21706126 is a wasteful number, since it uses less digits than its factorization.

21706126 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3267.

The product of its (nonzero) digits is 1008, while the sum is 25.

The square root of 21706126 is about 4658.9833654994. The cubic root of 21706126 is about 278.9506899319.

Adding to 21706126 its reverse (62160712), we get a palindrome (83866838).

The spelling of 21706126 in words is "twenty-one million, seven hundred six thousand, one hundred twenty-six".