21813456446 has 4 divisors (see below), whose sum is σ = 32720184672. Its totient is φ = 10906728222.

The previous prime is 21813456419. The next prime is 21813456461. The reversal of 21813456446 is 64465431812.

It is a semiprime because it is the product of two primes.

It is a junction number, because it is equal to n+sod(n) for n = 21813456397 and 21813456406.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 5453364110 + ... + 5453364113.

It is an arithmetic number, because the mean of its divisors is an integer number (8180046168).

Almost surely, 2^21813456446 is an apocalyptic number.

21813456446 is a deficient number, since it is larger than the sum of its proper divisors (10906728226).

21813456446 is a wasteful number, since it uses less digits than its factorization.

21813456446 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10906728225.

The product of its digits is 552960, while the sum is 44.

The spelling of 21813456446 in words is "twenty-one billion, eight hundred thirteen million, four hundred fifty-six thousand, four hundred forty-six".