21042440522 has 16 divisors (see below), whose sum is σ = 31699635072. Its totient is φ = 10475943840.

The previous prime is 21042440519. The next prime is 21042440539. The reversal of 21042440522 is 22504424012.

It is a junction number, because it is equal to n+sod(n) for n = 21042440491 and 21042440500.

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, 939053 + ... + 961199.

It is an arithmetic number, because the mean of its divisors is an integer number (1981227192).

Almost surely, 2^21042440522 is an apocalyptic number.

21042440522 is a deficient number, since it is larger than the sum of its proper divisors (10657194550).

21042440522 is a wasteful number, since it uses less digits than its factorization.

21042440522 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 24173.

The product of its (nonzero) digits is 5120, while the sum is 26.

Adding to 21042440522 its reverse (22504424012), we get a palindrome (43546864534).

The spelling of 21042440522 in words is "twenty-one billion, forty-two million, four hundred forty thousand, five hundred twenty-two".