21366242634542 has 32 divisors (see below), whose sum is σ = 36535207373280. Its totient is φ = 9299870939520.

The previous prime is 21366242634523. The next prime is 21366242634547. The reversal of 21366242634542 is 24543624266312.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21366242634547) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 329469809 + ... + 329534652.

It is an arithmetic number, because the mean of its divisors is an integer number (1141725230415).

Almost surely, 2^{21366242634542} is an apocalyptic number.

21366242634542 is a deficient number, since it is larger than the sum of its proper divisors (15168964738738).

21366242634542 is a wasteful number, since it uses less digits than its factorization.

21366242634542 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 659004548.

The product of its digits is 9953280, while the sum is 50.

The spelling of 21366242634542 in words is "twenty-one trillion, three hundred sixty-six billion, two hundred forty-two million, six hundred thirty-four thousand, five hundred forty-two".