21429286 has 4 divisors (see below), whose sum is σ = 32143932. Its totient is φ = 10714642.

The previous prime is 21429281. The next prime is 21429293. The reversal of 21429286 is 68292412.

It is a semiprime because it is the product of two primes.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21429281) 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 as a sum of consecutive naturals, namely, 5357320 + ... + 5357323.

It is an arithmetic number, because the mean of its divisors is an integer number (8035983).

Almost surely, 2^21429286 is an apocalyptic number.

21429286 is a deficient number, since it is larger than the sum of its proper divisors (10714646).

21429286 is a wasteful number, since it uses less digits than its factorization.

21429286 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10714645.

The product of its digits is 13824, while the sum is 34.

The square root of 21429286 is about 4629.1776807550. The cubic root of 21429286 is about 277.7596995286.

The spelling of 21429286 in words is "twenty-one million, four hundred twenty-nine thousand, two hundred eighty-six".