21738706 has 16 divisors (see below), whose sum is σ = 35663040. Its totient is φ = 9856080.

The previous prime is 21738701. The next prime is 21738707. The reversal of 21738706 is 60783712.

It is not an unprimeable number, because it can be changed into a prime (21738701) 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 7 ways as a sum of consecutive naturals, for example, 9700 + ... + 11728.

It is an arithmetic number, because the mean of its divisors is an integer number (2228940).

Almost surely, 2^21738706 is an apocalyptic number.

21738706 is a deficient number, since it is larger than the sum of its proper divisors (13924334).

21738706 is a wasteful number, since it uses less digits than its factorization.

21738706 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2529.

The product of its (nonzero) digits is 14112, while the sum is 34.

The square root of 21738706 is about 4662.4785254197. The cubic root of 21738706 is about 279.0901846573.

The spelling of 21738706 in words is "twenty-one million, seven hundred thirty-eight thousand, seven hundred six".