8991993 has 8 divisors (see below), whose sum is σ = 12244608. Its totient is φ = 5867024.

The previous prime is 8991991. The next prime is 8992007. The reversal of 8991993 is 3991998.

8991993 is digitally balanced in base 2 and base 4, because in such bases it contains all the possibile digits an equal number of times.

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

It is a cyclic number.

It is not a de Polignac number, because 8991993 - 2¹ = 8991991 is a prime.

It is a super-2 number, since 2×8991993² = 161711876224098, which contains 22 as substring.

8991993 is a lucky number.

It is not an unprimeable number, because it can be changed into a prime (8991991) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 31746 + ... + 32027.

It is an arithmetic number, because the mean of its divisors is an integer number (1530576).

Almost surely, 2^8991993 is an apocalyptic number.

It is an amenable number.

8991993 is a deficient number, since it is larger than the sum of its proper divisors (3252615).

8991993 is a wasteful number, since it uses less digits than its factorization.

8991993 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 63823.

The product of its digits is 157464, while the sum is 48.

The square root of 8991993 is about 2998.6652030529. The cubic root of 8991993 is about 207.9466779614.

The spelling of 8991993 in words is "eight million, nine hundred ninety-one thousand, nine hundred ninety-three".