21020626 has 8 divisors (see below), whose sum is σ = 34397424. Its totient is φ = 9554820.

The previous prime is 21020617. The next prime is 21020627. The reversal of 21020626 is 62602012.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not an unprimeable number, because it can be changed into a prime (21020627) 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 3 ways as a sum of consecutive naturals, for example, 477720 + ... + 477763.

It is an arithmetic number, because the mean of its divisors is an integer number (4299678).

Almost surely, 2^21020626 is an apocalyptic number.

21020626 is a deficient number, since it is larger than the sum of its proper divisors (13376798).

21020626 is a wasteful number, since it uses less digits than its factorization.

21020626 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 955496.

The product of its (nonzero) digits is 288, while the sum is 19.

The square root of 21020626 is about 4584.8256237288. The cubic root of 21020626 is about 275.9827143834.

Adding to 21020626 its reverse (62602012), we get a palindrome (83622638).

The spelling of 21020626 in words is "twenty-one million, twenty thousand, six hundred twenty-six".