997647649 has 4 divisors (see below), whose sum is σ = 1050155440. Its totient is φ = 945139860.

The previous prime is 997647643. The next prime is 997647671. The reversal of 997647649 is 946746799.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 997647649 - 2⁵ = 997647617 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (997647643) by changing a digit.

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, 26253867 + ... + 26253904.

It is an arithmetic number, because the mean of its divisors is an integer number (262538860).

Almost surely, 2^997647649 is an apocalyptic number.

It is an amenable number.

997647649 is a deficient number, since it is larger than the sum of its proper divisors (52507791).

997647649 is a wasteful number, since it uses less digits than its factorization.

997647649 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 52507790.

The product of its digits is 20575296, while the sum is 61.

The square root of 997647649 is about 31585.5607675406. The cubic root of 997647649 is about 999.2152673558.

The spelling of 997647649 in words is "nine hundred ninety-seven million, six hundred forty-seven thousand, six hundred forty-nine".