997478 has 4 divisors (see below), whose sum is σ = 1496220. Its totient is φ = 498738.

The previous prime is 997463. The next prime is 997511. The reversal of 997478 is 874799.

It is a semiprime because it is the product of two primes.

It is an Ulam number.

It is a congruent number.

It is an unprimeable number.

997478 is an untouchable number, because it is not equal to the sum of proper divisors of any number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 249368 + ... + 249371.

It is an arithmetic number, because the mean of its divisors is an integer number (374055).

2⁹⁹⁷⁴⁷⁸ is an apocalyptic number.

997478 is a deficient number, since it is larger than the sum of its proper divisors (498742).

997478 is a wasteful number, since it uses less digits than its factorization.

997478 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 498741.

The product of its digits is 127008, while the sum is 44.

The square root of 997478 is about 998.7382039353. The cubic root of 997478 is about 99.9158625621.

The spelling of 997478 in words is "nine hundred ninety-seven thousand, four hundred seventy-eight".