21012310544 has 20 divisors (see below), whose sum is σ = 41201852496. Its totient is φ = 10379574432.

The previous prime is 21012310507. The next prime is 21012310549. The reversal of 21012310544 is 44501321012.

It is not an unprimeable number, because it can be changed into a prime (21012310549) 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, 7909934 + ... + 7912589.

Almost surely, 2^21012310544 is an apocalyptic number.

It is an amenable number.

21012310544 is a deficient number, since it is larger than the sum of its proper divisors (20189541952).

21012310544 is a wasteful number, since it uses less digits than its factorization.

21012310544 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 15822614 (or 15822608 counting only the distinct ones).

The product of its (nonzero) digits is 960, while the sum is 23.

Adding to 21012310544 its reverse (44501321012), we get a palindrome (65513631556).

The spelling of 21012310544 in words is "twenty-one billion, twelve million, three hundred ten thousand, five hundred forty-four".