21086430 has 16 divisors (see below), whose sum is σ = 50607504. Its totient is φ = 5623040.

The previous prime is 21086413. The next prime is 21086431. The reversal of 21086430 is 3468012.

It is a happy number.

It is a self number, because there is not a number n which added to its sum of digits gives 21086430.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21086431) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 351411 + ... + 351470.

It is an arithmetic number, because the mean of its divisors is an integer number (3162969).

Almost surely, 2^21086430 is an apocalyptic number.

21086430 is an abundant number, since it is smaller than the sum of its proper divisors (29521074).

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

21086430 is a wasteful number, since it uses less digits than its factorization.

21086430 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 702891.

The product of its (nonzero) digits is 1152, while the sum is 24.

The square root of 21086430 is about 4591.9962979079. The cubic root of 21086430 is about 276.2703976803.

The spelling of 21086430 in words is "twenty-one million, eighty-six thousand, four hundred thirty".