21318626 has 24 divisors (see below), whose sum is σ = 38071440. Its totient is φ = 8922312.

The previous prime is 21318599. The next prime is 21318643. The reversal of 21318626 is 62681312.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 1685 + ... + 6743.

It is an arithmetic number, because the mean of its divisors is an integer number (1586310).

Almost surely, 2^21318626 is an apocalyptic number.

21318626 is a deficient number, since it is larger than the sum of its proper divisors (16752814).

21318626 is a wasteful number, since it uses less digits than its factorization.

21318626 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5118 (or 5111 counting only the distinct ones).

The product of its digits is 3456, while the sum is 29.

The square root of 21318626 is about 4617.2097634827. The cubic root of 21318626 is about 277.2807607422.

Adding to 21318626 its reverse (62681312), we get a palindrome (83999938).

The spelling of 21318626 in words is "twenty-one million, three hundred eighteen thousand, six hundred twenty-six".