21440255442 has 16 divisors (see below), whose sum is σ = 42937617792. Its totient is φ = 7137234000.

The previous prime is 21440255429. The next prime is 21440255453. The reversal of 21440255442 is 24455204412.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 2374573 + ... + 2383584.

It is an arithmetic number, because the mean of its divisors is an integer number (2683601112).

Almost surely, 2^21440255442 is an apocalyptic number.

21440255442 is an abundant number, since it is smaller than the sum of its proper divisors (21497362350).

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

21440255442 is a wasteful number, since it uses less digits than its factorization.

21440255442 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4758913.

The product of its (nonzero) digits is 51200, while the sum is 33.

Adding to 21440255442 its reverse (24455204412), we get a palindrome (45895459854).

The spelling of 21440255442 in words is "twenty-one billion, four hundred forty million, two hundred fifty-five thousand, four hundred forty-two".