21115234042 has 32 divisors (see below), whose sum is σ = 38989799424. Its totient is φ = 8376706800.

The previous prime is 21115233977. The next prime is 21115234067. The reversal of 21115234042 is 24043251112.

It is a junction number, because it is equal to n+sod(n) for n = 21115233998 and 21115234016.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1047684 + ... + 1067647.

It is an arithmetic number, because the mean of its divisors is an integer number (1218431232).

Almost surely, 2^21115234042 is an apocalyptic number.

21115234042 is a deficient number, since it is larger than the sum of its proper divisors (17874565382).

21115234042 is a wasteful number, since it uses less digits than its factorization.

21115234042 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2115394.

The product of its (nonzero) digits is 1920, while the sum is 25.

Adding to 21115234042 its reverse (24043251112), we get a palindrome (45158485154).

The spelling of 21115234042 in words is "twenty-one billion, one hundred fifteen million, two hundred thirty-four thousand, forty-two".