999993820 has 96 divisors (see below), whose sum is σ = 2500485120. Its totient is φ = 328769280.

The previous prime is 999993817. The next prime is 999993821. The reversal of 999993820 is 28399999.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (999993821) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 366421 + ... + 369139.

It is an arithmetic number, because the mean of its divisors is an integer number (26046720).

Almost surely, 2^999993820 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 999993820, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1250242560).

999993820 is an abundant number, since it is smaller than the sum of its proper divisors (1500491300).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

999993820 is a wasteful number, since it uses less digits than its factorization.

999993820 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2843 (or 2841 counting only the distinct ones).

The product of its (nonzero) digits is 2834352, while the sum is 58.

The square root of 999993820 is about 31622.6788871531. The cubic root of 999993820 is about 999.9979399958.

The spelling of 999993820 in words is "nine hundred ninety-nine million, nine hundred ninety-three thousand, eight hundred twenty".