21343505236 has 24 divisors (see below), whose sum is σ = 39634105896. Its totient is φ = 10022200320.

The previous prime is 21343505221. The next prime is 21343505237. The reversal of 21343505236 is 63250534312.

It can be written as a sum of positive squares in 4 ways, for example, as 273240900 + 21070264336 = 16530^2 + 145156^2 .

It is a Harshad number since it is a multiple of its sum of digits (34).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21343505237) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 309081 + ... + 371776.

It is an arithmetic number, because the mean of its divisors is an integer number (1651421079).

Almost surely, 2^21343505236 is an apocalyptic number.

It is an amenable number.

21343505236 is a deficient number, since it is larger than the sum of its proper divisors (18290600660).

21343505236 is a wasteful number, since it uses less digits than its factorization.

21343505236 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 681339 (or 681337 counting only the distinct ones).

The product of its (nonzero) digits is 64800, while the sum is 34.

The spelling of 21343505236 in words is "twenty-one billion, three hundred forty-three million, five hundred five thousand, two hundred thirty-six".