840990428 has 6 divisors (see below), whose sum is σ = 1471733256. Its totient is φ = 420495212.

The previous prime is 840990389. The next prime is 840990473. The reversal of 840990428 is 824099048.

It is a happy number.

840990428 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 105123800 + ... + 105123807.

It is an arithmetic number, because the mean of its divisors is an integer number (245288876).

Almost surely, 2^840990428 is an apocalyptic number.

It is an amenable number.

840990428 is a deficient number, since it is larger than the sum of its proper divisors (630742828).

840990428 is a wasteful number, since it uses less digits than its factorization.

840990428 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 210247611 (or 210247609 counting only the distinct ones).

The product of its (nonzero) digits is 165888, while the sum is 44.

The square root of 840990428 is about 28999.8349650476. The cubic root of 840990428 is about 943.9094866175.

The spelling of 840990428 in words is "eight hundred forty million, nine hundred ninety thousand, four hundred twenty-eight".