21431334 has 8 divisors (see below), whose sum is σ = 42862680. Its totient is φ = 7143776.

The previous prime is 21431317. The next prime is 21431341. The reversal of 21431334 is 43313412.

It is a sphenic number, since it is the product of 3 distinct primes.

21431334 is an admirable number.

It is a self number, because there is not a number n which added to its sum of digits gives 21431334.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1785939 + ... + 1785950.

It is an arithmetic number, because the mean of its divisors is an integer number (5357835).

Almost surely, 2^21431334 is an apocalyptic number.

21431334 is a primitive abundant number, since it is smaller than the sum of its proper divisors, none of which is abundant.

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

21431334 is a wasteful number, since it uses less digits than its factorization.

21431334 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3571894.

The product of its digits is 864, while the sum is 21.

The square root of 21431334 is about 4629.3988810644. The cubic root of 21431334 is about 277.7685477585.

Adding to 21431334 its reverse (43313412), we get a palindrome (64744746).

The spelling of 21431334 in words is "twenty-one million, four hundred thirty-one thousand, three hundred thirty-four".