21215345335 has 16 divisors (see below), whose sum is σ = 25532279136. Its totient is φ = 16923091968.

The previous prime is 21215345323. The next prime is 21215345377. The reversal of 21215345335 is 53354351212.

It is a cyclic number.

It is not a de Polignac number, because 21215345335 - 2⁵ = 21215345303 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 21215345335.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 4146739 + ... + 4151851.

It is an arithmetic number, because the mean of its divisors is an integer number (1595767446).

Almost surely, 2^21215345335 is an apocalyptic number.

21215345335 is a deficient number, since it is larger than the sum of its proper divisors (4316933801).

21215345335 is a wasteful number, since it uses less digits than its factorization.

21215345335 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7362.

The product of its digits is 54000, while the sum is 34.

Adding to 21215345335 its reverse (53354351212), we get a palindrome (74569696547).

The spelling of 21215345335 in words is "twenty-one billion, two hundred fifteen million, three hundred forty-five thousand, three hundred thirty-five".