840400378 has 4 divisors (see below), whose sum is σ = 1260600570. Its totient is φ = 420200188.

The previous prime is 840400369. The next prime is 840400403. The reversal of 840400378 is 873004048.

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

It can be written as a sum of positive squares in only one way, i.e., 620856889 + 219543489 = 24917^2 + 14817^2 .

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 210100093 + ... + 210100096.

Almost surely, 2^840400378 is an apocalyptic number.

840400378 is a deficient number, since it is larger than the sum of its proper divisors (420200192).

840400378 is a wasteful number, since it uses less digits than its factorization.

840400378 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 420200191.

The product of its (nonzero) digits is 21504, while the sum is 34.

The square root of 840400378 is about 28989.6598462279. The cubic root of 840400378 is about 943.6886818456.

The spelling of 840400378 in words is "eight hundred forty million, four hundred thousand, three hundred seventy-eight".