20001993 has 8 divisors (see below), whose sum is σ = 29093856. Its totient is φ = 12122400.

The previous prime is 20001983. The next prime is 20002007. The reversal of 20001993 is 39910002.

It is a happy number.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 20001993 - 2⁴ = 20001977 is a prime.

It is not an unprimeable number, because it can be changed into a prime (20001983) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 303028 + ... + 303093.

It is an arithmetic number, because the mean of its divisors is an integer number (3636732).

Almost surely, 2^20001993 is an apocalyptic number.

It is an amenable number.

20001993 is a deficient number, since it is larger than the sum of its proper divisors (9091863).

20001993 is a wasteful number, since it uses less digits than its factorization.

20001993 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 606135.

The product of its (nonzero) digits is 486, while the sum is 24.

The square root of 20001993 is about 4472.3587736227. The cubic root of 20001993 is about 271.4507777505.

Adding to 20001993 its reverse (39910002), we get a palindrome (59911995).

It can be divided in two parts, 2000 and 1993, that added together give a palindrome (3993).

The spelling of 20001993 in words is "twenty million, one thousand, nine hundred ninety-three".