997643786 has 16 divisors (see below), whose sum is σ = 1513284864. Its totient is φ = 493230384.

The previous prime is 997643747. The next prime is 997643831. The reversal of 997643786 is 687346799.

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 7 ways as a sum of consecutive naturals, for example, 147695 + ... + 154301.

It is an arithmetic number, because the mean of its divisors is an integer number (94580304).

Almost surely, 2^997643786 is an apocalyptic number.

997643786 is a deficient number, since it is larger than the sum of its proper divisors (515641078).

997643786 is a wasteful number, since it uses less digits than its factorization.

997643786 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7445.

The product of its digits is 13716864, while the sum is 59.

The square root of 997643786 is about 31585.4996161213. The cubic root of 997643786 is about 999.2139776641.

The spelling of 997643786 in words is "nine hundred ninety-seven million, six hundred forty-three thousand, seven hundred eighty-six".