331666993 has 4 divisors (see below), whose sum is σ = 379048000. Its totient is φ = 284285988.

The previous prime is 331666961. The next prime is 331667003. The reversal of 331666993 is 399666133.

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 not a de Polignac number, because 331666993 - 2⁵ = 331666961 is a prime.

It is a super-2 number, since 2×331666993² = 220005988491324098, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (331666903) 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, 23690493 + ... + 23690506.

It is an arithmetic number, because the mean of its divisors is an integer number (94762000).

Almost surely, 2^331666993 is an apocalyptic number.

It is an amenable number.

331666993 is a deficient number, since it is larger than the sum of its proper divisors (47381007).

331666993 is an equidigital number, since it uses as much as digits as its factorization.

331666993 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 47381006.

The product of its digits is 472392, while the sum is 46.

The square root of 331666993 is about 18211.7267989612. The cubic root of 331666993 is about 692.2039678795.

The spelling of 331666993 in words is "three hundred thirty-one million, six hundred sixty-six thousand, nine hundred ninety-three".