21676739 has 16 divisors (see below), whose sum is σ = 26208000. Its totient is φ = 17514144.

The previous prime is 21676703. The next prime is 21676747. The reversal of 21676739 is 93767612.

It is a cyclic number.

It is not a de Polignac number, because 21676739 - 2⁸ = 21676483 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 21676696 and 21676705.

It is not an unprimeable number, because it can be changed into a prime (21676799) 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 in 15 ways as a sum of consecutive naturals, for example, 46184 + ... + 46650.

It is an arithmetic number, because the mean of its divisors is an integer number (1638000).

Almost surely, 2^21676739 is an apocalyptic number.

21676739 is a deficient number, since it is larger than the sum of its proper divisors (4531261).

21676739 is a wasteful number, since it uses less digits than its factorization.

21676739 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 842.

The product of its digits is 95256, while the sum is 41.

The square root of 21676739 is about 4655.8284977005. The cubic root of 21676739 is about 278.8247465901.

The spelling of 21676739 in words is "twenty-one million, six hundred seventy-six thousand, seven hundred thirty-nine".