21082686 has 32 divisors (see below), whose sum is σ = 44997120. Its totient is φ = 6562176.

The previous prime is 21082673. The next prime is 21082687. The reversal of 21082686 is 68628012.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21082687) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 13435 + ... + 14921.

It is an arithmetic number, because the mean of its divisors is an integer number (1406160).

Almost surely, 2^21082686 is an apocalyptic number.

21082686 is an abundant number, since it is smaller than the sum of its proper divisors (23914434).

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

21082686 is a wasteful number, since it uses less digits than its factorization.

21082686 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1648.

The product of its (nonzero) digits is 9216, while the sum is 33.

The square root of 21082686 is about 4591.5886139766. The cubic root of 21082686 is about 276.2540456537.

The spelling of 21082686 in words is "twenty-one million, eighty-two thousand, six hundred eighty-six".