921536643 has 4 divisors (see below), whose sum is σ = 1228715528. Its totient is φ = 614357760.

The previous prime is 921536641. The next prime is 921536701. The reversal of 921536643 is 346635129.

921536643 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a semiprime because it is the product of two primes.

It is not a de Polignac number, because 921536643 - 2¹ = 921536641 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (921536641) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 153589438 + ... + 153589443.

It is an arithmetic number, because the mean of its divisors is an integer number (307178882).

Almost surely, 2^921536643 is an apocalyptic number.

921536643 is a deficient number, since it is larger than the sum of its proper divisors (307178885).

921536643 is a wasteful number, since it uses less digits than its factorization.

921536643 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 307178884.

The product of its digits is 116640, while the sum is 39.

The square root of 921536643 is about 30356.8220174642. The cubic root of 921536643 is about 973.1300184293.

The spelling of 921536643 in words is "nine hundred twenty-one million, five hundred thirty-six thousand, six hundred forty-three".