21335634645 has 32 divisors (see below), whose sum is σ = 36785223552. Its totient is φ = 10497330432.

The previous prime is 21335634613. The next prime is 21335634673. The reversal of 21335634645 is 54643653312.

It is not a de Polignac number, because 21335634645 - 2⁵ = 21335634613 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 21335634597 and 21335634606.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 297822 + ... + 362448.

It is an arithmetic number, because the mean of its divisors is an integer number (1149538236).

Almost surely, 2^21335634645 is an apocalyptic number.

It is an amenable number.

21335634645 is a deficient number, since it is larger than the sum of its proper divisors (15449588907).

21335634645 is a wasteful number, since it uses less digits than its factorization.

21335634645 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 66341.

The product of its digits is 777600, while the sum is 42.

The spelling of 21335634645 in words is "twenty-one billion, three hundred thirty-five million, six hundred thirty-four thousand, six hundred forty-five".