993947993 has 4 divisors (see below), whose sum is σ = 1052415540. Its totient is φ = 935480448.

The previous prime is 993947989. The next prime is 993948017. The reversal of 993947993 is 399749399.

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 396487744 + 597460249 = 19912^2 + 24443^2 .

It is a cyclic number.

It is not a de Polignac number, because 993947993 - 2² = 993947989 is a prime.

It is a super-2 number, since 2×993947993² = 1975865225577456098, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (993947923) 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, 29233748 + ... + 29233781.

It is an arithmetic number, because the mean of its divisors is an integer number (263103885).

Almost surely, 2^993947993 is an apocalyptic number.

It is an amenable number.

993947993 is a deficient number, since it is larger than the sum of its proper divisors (58467547).

993947993 is a wasteful number, since it uses less digits than its factorization.

993947993 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 58467546.

The product of its digits is 14880348, while the sum is 62.

The square root of 993947993 is about 31526.9407491434. The cubic root of 993947993 is about 997.9785809516.

The spelling of 993947993 in words is "nine hundred ninety-three million, nine hundred forty-seven thousand, nine hundred ninety-three".