21042140235524 has 12 divisors (see below), whose sum is σ = 37818981774924. Its totient is φ = 10236716871264.

The previous prime is 21042140235517. The next prime is 21042140235583. The reversal of 21042140235524 is 42553204124012.

It can be written as a sum of positive squares in 2 ways, for example, as 11217877476100 + 9824262759424 = 3349310^2 + 3134368^2 .

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 71088311459 + ... + 71088311754.

It is an arithmetic number, because the mean of its divisors is an integer number (3151581814577).

Almost surely, 2^{21042140235524} is an apocalyptic number.

It is an amenable number.

21042140235524 is a deficient number, since it is larger than the sum of its proper divisors (16776841539400).

21042140235524 is a wasteful number, since it uses less digits than its factorization.

21042140235524 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 142176623254 (or 142176623252 counting only the distinct ones).

The product of its (nonzero) digits is 76800, while the sum is 35.

Adding to 21042140235524 its reverse (42553204124012), we get a palindrome (63595344359536).

The spelling of 21042140235524 in words is "twenty-one trillion, forty-two billion, one hundred forty million, two hundred thirty-five thousand, five hundred twenty-four".