99428 has 24 divisors (see below), whose sum is σ = 205632. Its totient is φ = 41184.

The previous prime is 99409. The next prime is 99431. The reversal of 99428 is 82499.

It is a Smith number, since the sum of its digits (32) coincides with the sum of the digits of its prime factors.

It is a junction number, because it is equal to n+sod(n) for n = 99394 and 99403.

It is an unprimeable number.

99428 is an untouchable number, because it is not equal to the sum of proper divisors of any number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1451 + ... + 1517.

It is an arithmetic number, because the mean of its divisors is an integer number (8568).

2⁹⁹⁴²⁸ 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 99428, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (102816).

99428 is an abundant number, since it is smaller than the sum of its proper divisors (106204).

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

99428 is a wasteful number, since it uses less digits than its factorization.

99428 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 131 (or 129 counting only the distinct ones).

The product of its digits is 5184, while the sum is 32.

The square root of 99428 is about 315.3220575856. The cubic root of 99428 is about 46.3272194315.

The spelling of 99428 in words is "ninety-nine thousand, four hundred twenty-eight".