21426579 has 16 divisors (see below), whose sum is σ = 33611040. Its totient is φ = 13443840.

The previous prime is 21426553. The next prime is 21426583. The reversal of 21426579 is 97562412.

It is not a de Polignac number, because 21426579 - 2¹² = 21422483 is a prime.

It is a hoax number, since the sum of its digits (36) coincides with the sum of the digits of its distinct prime factors.

It is not an unprimeable number, because it can be changed into a prime (21422579) 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 15 ways as a sum of consecutive naturals, for example, 22882 + ... + 23799.

It is an arithmetic number, because the mean of its divisors is an integer number (2100690).

Almost surely, 2^21426579 is an apocalyptic number.

21426579 is a deficient number, since it is larger than the sum of its proper divisors (12184461).

21426579 is a wasteful number, since it uses less digits than its factorization.

21426579 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 46707 (or 46701 counting only the distinct ones).

The product of its digits is 30240, while the sum is 36.

The square root of 21426579 is about 4628.8852869778. The cubic root of 21426579 is about 277.7480032738.

The spelling of 21426579 in words is "twenty-one million, four hundred twenty-six thousand, five hundred seventy-nine".