19728993 has 16 divisors (see below), whose sum is σ = 28074816. Its totient is φ = 12280320.

The previous prime is 19728979. The next prime is 19729001. The reversal of 19728993 is 39982791.

It is not a de Polignac number, because 19728993 - 2²¹ = 17631841 is a prime.

It is not an unprimeable number, because it can be changed into a prime (19728953) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 5205 + ... + 8157.

It is an arithmetic number, because the mean of its divisors is an integer number (1754676).

Almost surely, 2^19728993 is an apocalyptic number.

It is an amenable number.

19728993 is a deficient number, since it is larger than the sum of its proper divisors (8345823).

19728993 is a wasteful number, since it uses less digits than its factorization.

19728993 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3104.

The product of its digits is 244944, while the sum is 48.

The square root of 19728993 is about 4441.7331076957. The cubic root of 19728993 is about 270.2101381925.

The spelling of 19728993 in words is "nineteen million, seven hundred twenty-eight thousand, nine hundred ninety-three".