21431384446 has 8 divisors (see below), whose sum is σ = 32155699464. Its totient is φ = 10712817960.

The previous prime is 21431384423. The next prime is 21431384461. The reversal of 21431384446 is 64448313412.

It is a happy number.

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

It is a junction number, because it is equal to n+sod(n) for n = 21431384399 and 21431384408.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1427800 + ... + 1442731.

It is an arithmetic number, because the mean of its divisors is an integer number (4019462433).

Almost surely, 2^21431384446 is an apocalyptic number.

21431384446 is a deficient number, since it is larger than the sum of its proper divisors (10724315018).

21431384446 is a wasteful number, since it uses less digits than its factorization.

21431384446 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2874266.

The product of its digits is 221184, while the sum is 40.

Adding to 21431384446 its reverse (64448313412), we get a palindrome (85879697858).

The spelling of 21431384446 in words is "twenty-one billion, four hundred thirty-one million, three hundred eighty-four thousand, four hundred forty-six".