21586242 has 16 divisors (see below), whose sum is σ = 45444960. Its totient is φ = 6816672.

The previous prime is 21586217. The next prime is 21586249. The reversal of 21586242 is 24268512.

It is not an unprimeable number, because it can be changed into a prime (21586249) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 94563 + ... + 94790.

It is an arithmetic number, because the mean of its divisors is an integer number (2840310).

Almost surely, 2^21586242 is an apocalyptic number.

21586242 is an abundant number, since it is smaller than the sum of its proper divisors (23858718).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

21586242 is a wasteful number, since it uses less digits than its factorization.

21586242 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 189377.

The product of its digits is 7680, while the sum is 30.

The square root of 21586242 is about 4646.0996545490. The cubic root of 21586242 is about 278.4361887740.

The spelling of 21586242 in words is "twenty-one million, five hundred eighty-six thousand, two hundred forty-two".