16993993 has 4 divisors (see below), whose sum is σ = 17106688. Its totient is φ = 16881300.

The previous prime is 16993969. The next prime is 16994009. The reversal of 16993993 is 39939961.

It is a happy number.

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.

It is a cyclic number.

It is not a de Polignac number, because 16993993 - 2¹⁷ = 16862921 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (16993903) 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 3 ways as a sum of consecutive naturals, for example, 56121 + ... + 56422.

It is an arithmetic number, because the mean of its divisors is an integer number (4276672).

Almost surely, 2^16993993 is an apocalyptic number.

It is an amenable number.

16993993 is a deficient number, since it is larger than the sum of its proper divisors (112695).

16993993 is a wasteful number, since it uses less digits than its factorization.

16993993 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 112694.

The product of its digits is 354294, while the sum is 49.

The square root of 16993993 is about 4122.3771055060. The cubic root of 16993993 is about 257.0978698342.

It can be divided in two parts, 16 and 993993, that added together give a square (994009 = 997²).

The spelling of 16993993 in words is "sixteen million, nine hundred ninety-three thousand, nine hundred ninety-three".