993943921 has 8 divisors (see below), whose sum is σ = 1021564800. Its totient is φ = 966592848.

The previous prime is 993943897. The next prime is 993943933. The reversal of 993943921 is 129349399.

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 993943921 - 2¹³ = 993935729 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (993943961) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 59971 + ... + 74728.

It is an arithmetic number, because the mean of its divisors is an integer number (127695600).

Almost surely, 2^993943921 is an apocalyptic number.

It is an amenable number.

993943921 is a deficient number, since it is larger than the sum of its proper divisors (27620879).

993943921 is a wasteful number, since it uses less digits than its factorization.

993943921 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 134903.

The product of its digits is 472392, while the sum is 49.

The square root of 993943921 is about 31526.8761693892. The cubic root of 993943921 is about 997.9772181123.

The spelling of 993943921 in words is "nine hundred ninety-three million, nine hundred forty-three thousand, nine hundred twenty-one".