38663993 has 4 divisors (see below), whose sum is σ = 40698960. Its totient is φ = 36629028.

The previous prime is 38663983. The next prime is 38664011. The reversal of 38663993 is 39936683.

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: 39936683 = 29 ⋅1377127.

It is a cyclic number.

It is not a de Polignac number, because 38663993 - 2¹⁶ = 38598457 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (38663983) 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, 1017455 + ... + 1017492.

It is an arithmetic number, because the mean of its divisors is an integer number (10174740).

Almost surely, 2^38663993 is an apocalyptic number.

It is an amenable number.

38663993 is a deficient number, since it is larger than the sum of its proper divisors (2034967).

38663993 is a wasteful number, since it uses less digits than its factorization.

38663993 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2034966.

The product of its digits is 629856, while the sum is 47.

The square root of 38663993 is about 6218.0377129767. The cubic root of 38663993 is about 338.1444272660.

The spelling of 38663993 in words is "thirty-eight million, six hundred sixty-three thousand, nine hundred ninety-three".