840736649 has 4 divisors (see below), whose sum is σ = 890191764. Its totient is φ = 791281536.

The previous prime is 840736627. The next prime is 840736679. The reversal of 840736649 is 946637048.

840736649 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 509314624 + 331422025 = 22568^2 + 18205^2 .

It is a cyclic number.

It is not a de Polignac number, because 840736649 - 2²⁸ = 572301193 is a prime.

It is a super-2 number, since 2×840736649² = 1413676225943498402, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (840736679) 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, 24727532 + ... + 24727565.

It is an arithmetic number, because the mean of its divisors is an integer number (222547941).

Almost surely, 2^840736649 is an apocalyptic number.

It is an amenable number.

840736649 is a deficient number, since it is larger than the sum of its proper divisors (49455115).

840736649 is a wasteful number, since it uses less digits than its factorization.

840736649 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 49455114.

The product of its (nonzero) digits is 870912, while the sum is 47.

The square root of 840736649 is about 28995.4591100055. The cubic root of 840736649 is about 943.8145317100.

The spelling of 840736649 in words is "eight hundred forty million, seven hundred thirty-six thousand, six hundred forty-nine".