999428 has 6 divisors (see below), whose sum is σ = 1749006. Its totient is φ = 499712.

The previous prime is 999389. The next prime is 999431. The reversal of 999428 is 824999.

It can be written as a sum of positive squares in only one way, i.e., 925444 + 73984 = 962^2 + 272^2 .

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 999428.

It is an unprimeable number.

999428 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 as a sum of consecutive naturals, namely, 124925 + ... + 124932.

It is an arithmetic number, because the mean of its divisors is an integer number (291501).

2⁹⁹⁹⁴²⁸ is an apocalyptic number.

It is an amenable number.

999428 is a deficient number, since it is larger than the sum of its proper divisors (749578).

999428 is a wasteful number, since it uses less digits than its factorization.

999428 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 249861 (or 249859 counting only the distinct ones).

The product of its digits is 46656, while the sum is 41.

The square root of 999428 is about 999.7139590903. The cubic root of 999428 is about 99.9809296968.

The spelling of 999428 in words is "nine hundred ninety-nine thousand, four hundred twenty-eight".