840813242 has 4 divisors (see below), whose sum is σ = 1261219866. Its totient is φ = 420406620.

The previous prime is 840813241. The next prime is 840813257. The reversal of 840813242 is 242318048.

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., 824321521 + 16491721 = 28711^2 + 4061^2 .

It is a junction number, because it is equal to n+sod(n) for n = 840813199 and 840813208.

It is not an unprimeable number, because it can be changed into a prime (840813241) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 210203309 + ... + 210203312.

Almost surely, 2^840813242 is an apocalyptic number.

840813242 is a deficient number, since it is larger than the sum of its proper divisors (420406624).

840813242 is a wasteful number, since it uses less digits than its factorization.

840813242 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 420406623.

The product of its (nonzero) digits is 12288, while the sum is 32.

The square root of 840813242 is about 28996.7798557012. The cubic root of 840813242 is about 943.8431920487.

The spelling of 840813242 in words is "eight hundred forty million, eight hundred thirteen thousand, two hundred forty-two".