840220428 has 24 divisors (see below), whose sum is σ = 1961874432. Its totient is φ = 279879184.

The previous prime is 840220417. The next prime is 840220439. The reversal of 840220428 is 824022048.

It is an interprime number because it is at equal distance from previous prime (840220417) and next prime (840220439).

It is a super-3 number, since 3×840220428³ (a number of 28 digits) contains 333 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 840220395 and 840220404.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 5700 + ... + 41387.

It is an arithmetic number, because the mean of its divisors is an integer number (81744768).

Almost surely, 2^840220428 is an apocalyptic number.

It is an amenable number.

840220428 is an abundant number, since it is smaller than the sum of its proper divisors (1121654004).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

840220428 is a wasteful number, since it uses less digits than its factorization.

840220428 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 48581 (or 48579 counting only the distinct ones).

The product of its (nonzero) digits is 8192, while the sum is 30.

The square root of 840220428 is about 28986.5559872159. Note that the first 3 decimals coincide. The cubic root of 840220428 is about 943.6213215315.

The spelling of 840220428 in words is "eight hundred forty million, two hundred twenty thousand, four hundred twenty-eight".