99821385 has 48 divisors (see below), whose sum is σ = 177465600. Its totient is φ = 51891840.

The previous prime is 99821369. The next prime is 99821401. The reversal of 99821385 is 58312899.

It is a happy number.

99821385 is a nontrivial binomial coefficient, being equal to C(14130, 2).

It is an interprime number because it is at equal distance from previous prime (99821369) and next prime (99821401).

It is not a de Polignac number, because 99821385 - 2⁴ = 99821369 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (45).

It is a Curzon number.

It is a self number, because there is not a number n which added to its sum of digits gives 99821385.

It is an unprimeable number.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 501516 + ... + 501714.

It is an arithmetic number, because the mean of its divisors is an integer number (3697200).

Almost surely, 2^99821385 is an apocalyptic number.

99821385 is the 14129-th triangular number and also the 7065-th hexagonal number.

It is an amenable number.

99821385 is a deficient number, since it is larger than the sum of its proper divisors (77644215).

99821385 is a wasteful number, since it uses less digits than its factorization.

99821385 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 438 (or 435 counting only the distinct ones).

The product of its digits is 155520, while the sum is 45.

The square root of 99821385 is about 9991.0652585197. The cubic root of 99821385 is about 463.8823661990.

The spelling of 99821385 in words is "ninety-nine million, eight hundred twenty-one thousand, three hundred eighty-five".