840778090 has 8 divisors (see below), whose sum is σ = 1513400580. Its totient is φ = 336311232.

The previous prime is 840778079. The next prime is 840778091. The reversal of 840778090 is 90877048.

It can be written as a sum of positive squares in 2 ways, for example, as 840594049 + 184041 = 28993^2 + 429^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is not an unprimeable number, because it can be changed into a prime (840778091) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 42038895 + ... + 42038914.

Almost surely, 2^840778090 is an apocalyptic number.

840778090 is a deficient number, since it is larger than the sum of its proper divisors (672622490).

840778090 is a wasteful number, since it uses less digits than its factorization.

840778090 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 84077816.

The product of its (nonzero) digits is 112896, while the sum is 43.

The square root of 840778090 is about 28996.1737130953. The cubic root of 840778090 is about 943.8300387361.

The spelling of 840778090 in words is "eight hundred forty million, seven hundred seventy-eight thousand, ninety".