388411993 has 4 divisors (see below), whose sum is σ = 401805540. Its totient is φ = 375018448.

The previous prime is 388411979. The next prime is 388411997. The reversal of 388411993 is 399114883.

It is a happy number.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 399114883 = 23 ⋅17352821.

It can be written as a sum of positive squares in 2 ways, for example, as 225390169 + 163021824 = 15013^2 + 12768^2 .

It is a cyclic number.

It is not a de Polignac number, because 388411993 - 2⁹ = 388411481 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (388411997) 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, 6696730 + ... + 6696787.

It is an arithmetic number, because the mean of its divisors is an integer number (100451385).

Almost surely, 2^388411993 is an apocalyptic number.

It is an amenable number.

388411993 is a deficient number, since it is larger than the sum of its proper divisors (13393547).

388411993 is a wasteful number, since it uses less digits than its factorization.

388411993 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 13393546.

The product of its digits is 186624, while the sum is 46.

The square root of 388411993 is about 19708.1707167357. The cubic root of 388411993 is about 729.6213667912.

The spelling of 388411993 in words is "three hundred eighty-eight million, four hundred eleven thousand, nine hundred ninety-three".