99784381 has 8 divisors (see below), whose sum is σ = 105400064. Its totient is φ = 94318560.

The previous prime is 99784379. The next prime is 99784387. The reversal of 99784381 is 18348799.

It is a happy number.

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 99784381 - 2¹ = 99784379 is a prime.

It is a super-2 number, since 2×99784381² = 19913845383106322, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (99784387) 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, 36096 + ... + 38761.

It is an arithmetic number, because the mean of its divisors is an integer number (13175008).

Almost surely, 2^99784381 is an apocalyptic number.

It is an amenable number.

99784381 is a deficient number, since it is larger than the sum of its proper divisors (5615683).

99784381 is a wasteful number, since it uses less digits than its factorization.

99784381 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 74931.

The product of its digits is 435456, while the sum is 49.

The square root of 99784381 is about 9989.2132322821. The cubic root of 99784381 is about 463.8250383875.

The spelling of 99784381 in words is "ninety-nine million, seven hundred eighty-four thousand, three hundred eighty-one".