999478 has 4 divisors (see below), whose sum is σ = 1499220. Its totient is φ = 499738.

The previous prime is 999451. The next prime is 999491. The reversal of 999478 is 874999.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 874999 = 47 ⋅18617.

It is a congruent number.

It is an unprimeable number.

999478 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, 249868 + ... + 249871.

It is an arithmetic number, because the mean of its divisors is an integer number (374805).

2⁹⁹⁹⁴⁷⁸ is an apocalyptic number.

999478 is a deficient number, since it is larger than the sum of its proper divisors (499742).

999478 is a wasteful number, since it uses less digits than its factorization.

999478 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 499741.

The product of its digits is 163296, while the sum is 46.

The square root of 999478 is about 999.7389659306. The cubic root of 999478 is about 99.9825969715.

The spelling of 999478 in words is "nine hundred ninety-nine thousand, four hundred seventy-eight".