938978993 has 4 divisors (see below), whose sum is σ = 988398960. Its totient is φ = 889559028.

The previous prime is 938978981. The next prime is 938979011. The reversal of 938978993 is 399879839.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 399879839 = 3301 ⋅121139.

It is a cyclic number.

It is not a de Polignac number, because 938978993 - 2⁴ = 938978977 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (938978093) 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, 24709955 + ... + 24709992.

It is an arithmetic number, because the mean of its divisors is an integer number (247099740).

Almost surely, 2^938978993 is an apocalyptic number.

It is an amenable number.

938978993 is a deficient number, since it is larger than the sum of its proper divisors (49419967).

938978993 is a wasteful number, since it uses less digits than its factorization.

938978993 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 49419966.

The product of its digits is 26453952, while the sum is 65.

The square root of 938978993 is about 30642.7641214039. The cubic root of 938978993 is about 979.2313120448.

The spelling of 938978993 in words is "nine hundred thirty-eight million, nine hundred seventy-eight thousand, nine hundred ninety-three".