21243145602 has 16 divisors (see below), whose sum is σ = 48555761472. Its totient is φ = 6069470160.

The previous prime is 21243145559. The next prime is 21243145619. The reversal of 21243145602 is 20654134212.

It is a self number, because there is not a number n which added to its sum of digits gives 21243145602.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 252894549 + ... + 252894632.

It is an arithmetic number, because the mean of its divisors is an integer number (3034735092).

Almost surely, 2^21243145602 is an apocalyptic number.

21243145602 is an abundant number, since it is smaller than the sum of its proper divisors (27312615870).

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

21243145602 is a wasteful number, since it uses less digits than its factorization.

21243145602 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 505789193.

The product of its (nonzero) digits is 11520, while the sum is 30.

Adding to 21243145602 its reverse (20654134212), we get a palindrome (41897279814).

The spelling of 21243145602 in words is "twenty-one billion, two hundred forty-three million, one hundred forty-five thousand, six hundred two".