840664733 has 4 divisors (see below), whose sum is σ = 843936060. Its totient is φ = 837393408.

The previous prime is 840664691. The next prime is 840664771. The reversal of 840664733 is 337466048.

840664733 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 can be written as a sum of positive squares in 2 ways, for example, as 580713604 + 259951129 = 24098^2 + 16123^2 .

It is a cyclic number.

It is not a de Polignac number, because 840664733 - 2¹⁰ = 840663709 is a prime.

It is a super-2 number, since 2×840664733² = 1413434386619922578, which contains 22 as substring.

It is a Duffinian number.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (840664133) 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, 1635278 + ... + 1635791.

It is an arithmetic number, because the mean of its divisors is an integer number (210984015).

Almost surely, 2^840664733 is an apocalyptic number.

It is an amenable number.

840664733 is a deficient number, since it is larger than the sum of its proper divisors (3271327).

840664733 is a wasteful number, since it uses less digits than its factorization.

840664733 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3271326.

The product of its (nonzero) digits is 290304, while the sum is 41.

The square root of 840664733 is about 28994.2189582682. The cubic root of 840664733 is about 943.7876198737.

The spelling of 840664733 in words is "eight hundred forty million, six hundred sixty-four thousand, seven hundred thirty-three".