21328436446 has 8 divisors (see below), whose sum is σ = 31996008144. Its totient is φ = 10663100400.

The previous prime is 21328436443. The next prime is 21328436513. The reversal of 21328436446 is 64463482312.

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

It is a super-2 number, since 2×21328436446² (a number of 21 digits) contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21328436443) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 534855 + ... + 573346.

It is an arithmetic number, because the mean of its divisors is an integer number (3999501018).

Almost surely, 2^21328436446 is an apocalyptic number.

21328436446 is a deficient number, since it is larger than the sum of its proper divisors (10667571698).

21328436446 is a wasteful number, since it uses less digits than its factorization.

21328436446 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1117826.

The product of its digits is 663552, while the sum is 43.

The spelling of 21328436446 in words is "twenty-one billion, three hundred twenty-eight million, four hundred thirty-six thousand, four hundred forty-six".