20199728 has 10 divisors (see below), whose sum is σ = 39137004. Its totient is φ = 10099856.

The previous prime is 20199709. The next prime is 20199737. The reversal of 20199728 is 82799102.

It is a super-2 number, since 2×20199728² = 816058022547968, which contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 20199691 and 20199700.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 631226 + ... + 631257.

Almost surely, 2^20199728 is an apocalyptic number.

It is an amenable number.

20199728 is a deficient number, since it is larger than the sum of its proper divisors (18937276).

20199728 is a wasteful number, since it uses less digits than its factorization.

20199728 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1262491 (or 1262485 counting only the distinct ones).

The product of its (nonzero) digits is 18144, while the sum is 38.

The square root of 20199728 is about 4494.4107511441. The cubic root of 20199728 is about 272.3423457512.

The spelling of 20199728 in words is "twenty million, one hundred ninety-nine thousand, seven hundred twenty-eight".