21013332444 has 48 divisors (see below), whose sum is σ = 58669707040. Its totient is φ = 6465640320.

The previous prime is 21013332419. The next prime is 21013332533. The reversal of 21013332444 is 44423331012.

21013332444 is a `hidden beast` number, since 210 + 1 + 3 + 3 + 3 + 2 + 444 = 666.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 7481977 + ... + 7484784.

Almost surely, 2^21013332444 is an apocalyptic number.

It is an amenable number.

21013332444 is an abundant number, since it is smaller than the sum of its proper divisors (37656374596).

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

21013332444 is a wasteful number, since it uses less digits than its factorization.

21013332444 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 14966787 (or 14966779 counting only the distinct ones).

The product of its (nonzero) digits is 6912, while the sum is 27.

Adding to 21013332444 its reverse (44423331012), we get a palindrome (65436663456).

The spelling of 21013332444 in words is "twenty-one billion, thirteen million, three hundred thirty-two thousand, four hundred forty-four".