997643785 has 8 divisors (see below), whose sum is σ = 1197649800. Its totient is φ = 797796864.

The previous prime is 997643747. The next prime is 997643831. The reversal of 997643785 is 587346799.

It can be written as a sum of positive squares in 4 ways, for example, as 201952521 + 795691264 = 14211^2 + 28208^2 .

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

It is a cyclic number.

It is not a de Polignac number, because 997643785 - 2¹⁷ = 997512713 is a prime.

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, 25510 + ... + 51439.

It is an arithmetic number, because the mean of its divisors is an integer number (149706225).

Almost surely, 2^997643785 is an apocalyptic number.

It is an amenable number.

997643785 is a deficient number, since it is larger than the sum of its proper divisors (200006015).

997643785 is a wasteful number, since it uses less digits than its factorization.

997643785 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 79547.

The product of its digits is 11430720, while the sum is 58.

The square root of 997643785 is about 31585.4996002913. The cubic root of 997643785 is about 999.2139773302.

The spelling of 997643785 in words is "nine hundred ninety-seven million, six hundred forty-three thousand, seven hundred eighty-five".