21305524042 has 8 divisors (see below), whose sum is σ = 34863584832. Its totient is φ = 9684329100.

The previous prime is 21305523997. The next prime is 21305524069. The reversal of 21305524042 is 24042550312.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a self number, because there is not a number n which added to its sum of digits gives 21305524042.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 484216434 + ... + 484216477.

It is an arithmetic number, because the mean of its divisors is an integer number (4357948104).

Almost surely, 2^21305524042 is an apocalyptic number.

21305524042 is a gapful number since it is divisible by the number (22) formed by its first and last digit.

21305524042 is a deficient number, since it is larger than the sum of its proper divisors (13558060790).

21305524042 is a wasteful number, since it uses less digits than its factorization.

21305524042 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 968432924.

The product of its (nonzero) digits is 9600, while the sum is 28.

The spelling of 21305524042 in words is "twenty-one billion, three hundred five million, five hundred twenty-four thousand, forty-two".