999321421 has 16 divisors (see below), whose sum is σ = 1214576640. Its totient is φ = 802632960.

The previous prime is 999321403. The next prime is 999321431. The reversal of 999321421 is 124123999.

It is a cyclic number.

It is not a de Polignac number, because 999321421 - 2¹⁷ = 999190349 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (999321431) 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 15 ways as a sum of consecutive naturals, for example, 8916 + ... + 45586.

It is an arithmetic number, because the mean of its divisors is an integer number (75911040).

Almost surely, 2^999321421 is an apocalyptic number.

It is an amenable number.

999321421 is a deficient number, since it is larger than the sum of its proper divisors (215255219).

999321421 is a wasteful number, since it uses less digits than its factorization.

999321421 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 36924.

The product of its digits is 34992, while the sum is 40.

The square root of 999321421 is about 31612.0455048388. The cubic root of 999321421 is about 999.7737558174.

The spelling of 999321421 in words is "nine hundred ninety-nine million, three hundred twenty-one thousand, four hundred twenty-one".