21431467 has 8 divisors (see below), whose sum is σ = 21874320. Its totient is φ = 20993280.

The previous prime is 21431401. The next prime is 21431489. The reversal of 21431467 is 76413412.

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

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21431467 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21431497) 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, 8992 + ... + 11122.

It is an arithmetic number, because the mean of its divisors is an integer number (2734290).

Almost surely, 2^21431467 is an apocalyptic number.

21431467 is a deficient number, since it is larger than the sum of its proper divisors (442853).

21431467 is a wasteful number, since it uses less digits than its factorization.

21431467 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2333.

The product of its digits is 4032, while the sum is 28.

The square root of 21431467 is about 4629.4132457580. The cubic root of 21431467 is about 277.7691223555.

Adding to 21431467 its reverse (76413412), we get a palindrome (97844879).

The spelling of 21431467 in words is "twenty-one million, four hundred thirty-one thousand, four hundred sixty-seven".