840020428 has 24 divisors (see below), whose sum is σ = 1587465152. Its totient is φ = 386636544.

The previous prime is 840020413. The next prime is 840020431. The reversal of 840020428 is 824020048.

It is a junction number, because it is equal to n+sod(n) for n = 840020396 and 840020405.

It is an unprimeable number.

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 7 ways as a sum of consecutive naturals, for example, 2925 + ... + 41092.

Almost surely, 2^840020428 is an apocalyptic number.

It is an amenable number.

840020428 is a deficient number, since it is larger than the sum of its proper divisors (747444724).

840020428 is a wasteful number, since it uses less digits than its factorization.

840020428 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 44401 (or 44399 counting only the distinct ones).

The product of its (nonzero) digits is 4096, while the sum is 28.

The square root of 840020428 is about 28983.1059067175. The cubic root of 840020428 is about 943.5464446563.

The spelling of 840020428 in words is "eight hundred forty million, twenty thousand, four hundred twenty-eight".