997699478 has 4 divisors (see below), whose sum is σ = 1496549220. Its totient is φ = 498849738.

The previous prime is 997699463. The next prime is 997699511. The reversal of 997699478 is 874996799.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 874996799 = 139 ⋅6294941.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 249424868 + ... + 249424871.

It is an arithmetic number, because the mean of its divisors is an integer number (374137305).

Almost surely, 2^997699478 is an apocalyptic number.

997699478 is a deficient number, since it is larger than the sum of its proper divisors (498849742).

997699478 is a wasteful number, since it uses less digits than its factorization.

997699478 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 498849741.

The product of its digits is 61725888, while the sum is 68.

The square root of 997699478 is about 31586.3812108953. The cubic root of 997699478 is about 999.2325705360.

The spelling of 997699478 in words is "nine hundred ninety-seven million, six hundred ninety-nine thousand, four hundred seventy-eight".