21440423012 has 12 divisors (see below), whose sum is σ = 37670227056. Its totient is φ = 10677501000.

The previous prime is 21440423009. The next prime is 21440423021. The reversal of 21440423012 is 21032404412.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 10676498 + ... + 10678505.

It is an arithmetic number, because the mean of its divisors is an integer number (3139185588).

Almost surely, 2^21440423012 is an apocalyptic number.

It is an amenable number.

21440423012 is a deficient number, since it is larger than the sum of its proper divisors (16229804044).

21440423012 is a wasteful number, since it uses less digits than its factorization.

21440423012 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 21355258 (or 21355256 counting only the distinct ones).

The product of its (nonzero) digits is 1536, while the sum is 23.

Adding to 21440423012 its reverse (21032404412), we get a palindrome (42472827424).

The spelling of 21440423012 in words is "twenty-one billion, four hundred forty million, four hundred twenty-three thousand, twelve".