991647442 has 8 divisors (see below), whose sum is σ = 1490860800. Its totient is φ = 494693844.

The previous prime is 991647427. The next prime is 991647469. The reversal of 991647442 is 244746199.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a junction number, because it is equal to n+sod(n) for n = 991647392 and 991647401.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 563842 + ... + 565597.

It is an arithmetic number, because the mean of its divisors is an integer number (186357600).

Almost surely, 2^991647442 is an apocalyptic number.

991647442 is a deficient number, since it is larger than the sum of its proper divisors (499213358).

991647442 is a wasteful number, since it uses less digits than its factorization.

991647442 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1129880.

The product of its digits is 435456, while the sum is 46.

The square root of 991647442 is about 31490.4341348289. The cubic root of 991647442 is about 997.2080261365.

The spelling of 991647442 in words is "nine hundred ninety-one million, six hundred forty-seven thousand, four hundred forty-two".