1991699828 has 12 divisors (see below), whose sum is σ = 3486124992. Its totient is φ = 995664120.

The previous prime is 1991699813. The next prime is 1991699851. The reversal of 1991699828 is 8289961991.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 20750 + ... + 66437.

It is an arithmetic number, because the mean of its divisors is an integer number (290510416).

Almost surely, 2^1991699828 is an apocalyptic number.

It is an amenable number.

1991699828 is a deficient number, since it is larger than the sum of its proper divisors (1494425164).

1991699828 is a wasteful number, since it uses less digits than its factorization.

1991699828 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 92902 (or 92900 counting only the distinct ones).

The product of its digits is 5038848, while the sum is 62.

The square root of 1991699828 is about 44628.4643249126. The cubic root of 1991699828 is about 1258.1757063181.

The spelling of 1991699828 in words is "one billion, nine hundred ninety-one million, six hundred ninety-nine thousand, eight hundred twenty-eight".