19905828 has 24 divisors (see below), whose sum is σ = 47580960. Its totient is φ = 6473280.

The previous prime is 19905817. The next prime is 19905839. The reversal of 19905828 is 82850991.

It is a happy number.

It is an interprime number because it is at equal distance from previous prime (19905817) and next prime (19905839).

It is a self number, because there is not a number n which added to its sum of digits gives 19905828.

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, 19738 + ... + 20721.

It is an arithmetic number, because the mean of its divisors is an integer number (1982540).

Almost surely, 2^19905828 is an apocalyptic number.

It is an amenable number.

19905828 is an abundant number, since it is smaller than the sum of its proper divisors (27675132).

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

19905828 is a wasteful number, since it uses less digits than its factorization.

19905828 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 40507 (or 40505 counting only the distinct ones).

The product of its (nonzero) digits is 51840, while the sum is 42.

The square root of 19905828 is about 4461.5947821379. The cubic root of 19905828 is about 271.0150543327.

The spelling of 19905828 in words is "nineteen million, nine hundred five thousand, eight hundred twenty-eight".