997305887 has 4 divisors (see below), whose sum is σ = 997459536. Its totient is φ = 997152240.

The previous prime is 997305871. The next prime is 997305893. The reversal of 997305887 is 788503799.

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

It is a cyclic number.

It is not a de Polignac number, because 997305887 - 2⁴ = 997305871 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (997305817) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 66638 + ... + 80219.

It is an arithmetic number, because the mean of its divisors is an integer number (249364884).

Almost surely, 2^997305887 is an apocalyptic number.

997305887 is a deficient number, since it is larger than the sum of its proper divisors (153649).

997305887 is a wasteful number, since it uses less digits than its factorization.

997305887 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 153648.

The product of its (nonzero) digits is 3810240, while the sum is 56.

The square root of 997305887 is about 31580.1502054693. The cubic root of 997305887 is about 999.1011546524.

The spelling of 997305887 in words is "nine hundred ninety-seven million, three hundred five thousand, eight hundred eighty-seven".