19727993 has 4 divisors (see below), whose sum is σ = 20261220. Its totient is φ = 19194768.

The previous prime is 19727977. The next prime is 19728017. The reversal of 19727993 is 39972791.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 19035769 + 692224 = 4363^2 + 832^2 .

It is a cyclic number.

It is not a de Polignac number, because 19727993 - 2⁴ = 19727977 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (19727933) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 266558 + ... + 266631.

It is an arithmetic number, because the mean of its divisors is an integer number (5065305).

Almost surely, 2^19727993 is an apocalyptic number.

It is an amenable number.

19727993 is a deficient number, since it is larger than the sum of its proper divisors (533227).

19727993 is an equidigital number, since it uses as much as digits as its factorization.

19727993 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 533226.

The product of its digits is 214326, while the sum is 47.

The square root of 19727993 is about 4441.6205375966. The cubic root of 19727993 is about 270.2055727507.

The spelling of 19727993 in words is "nineteen million, seven hundred twenty-seven thousand, nine hundred ninety-three".