21051232342542 has 32 divisors (see below), whose sum is σ = 47306140106400. Its totient is φ = 6938233879104.

The previous prime is 21051232342541. The next prime is 21051232342559. The reversal of 21051232342542 is 24524323215012.

21051232342542 is a `hidden beast` number, since 2 + 1 + 0 + 51 + 2 + 3 + 23 + 42 + 542 = 666.

It is a junction number, because it is equal to n+sod(n) for n = 21051232342497 and 21051232342506.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21051232342541) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 2190094273 + ... + 2190103884.

It is an arithmetic number, because the mean of its divisors is an integer number (1478316878325).

Almost surely, 2^{21051232342542} is an apocalyptic number.

21051232342542 is an abundant number, since it is smaller than the sum of its proper divisors (26254907763858).

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

21051232342542 is a wasteful number, since it uses less digits than its factorization.

21051232342542 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4380198257 (or 4380198251 counting only the distinct ones).

The product of its (nonzero) digits is 115200, while the sum is 36.

Adding to 21051232342542 its reverse (24524323215012), we get a palindrome (45575555557554).

The spelling of 21051232342542 in words is "twenty-one trillion, fifty-one billion, two hundred thirty-two million, three hundred forty-two thousand, five hundred forty-two".