21324685 has 16 divisors (see below), whose sum is σ = 26248320. Its totient is φ = 16626240.

The previous prime is 21324671. The next prime is 21324701. The reversal of 21324685 is 58642312.

It is not a de Polignac number, because 21324685 - 2⁷ = 21324557 is a prime.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 42144 + ... + 42646.

It is an arithmetic number, because the mean of its divisors is an integer number (1640520).

Almost surely, 2^21324685 is an apocalyptic number.

It is an amenable number.

21324685 is a deficient number, since it is larger than the sum of its proper divisors (4923635).

21324685 is a wasteful number, since it uses less digits than its factorization.

21324685 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 708.

The product of its digits is 11520, while the sum is 31.

The square root of 21324685 is about 4617.8658490692. The cubic root of 21324685 is about 277.3070270534.

Adding to 21324685 its reverse (58642312), we get a palindrome (79966997).

The spelling of 21324685 in words is "twenty-one million, three hundred twenty-four thousand, six hundred eighty-five".