997646989 has 8 divisors (see below), whose sum is σ = 1074237120. Its totient is φ = 923046336.

The previous prime is 997646987. The next prime is 997647031. The reversal of 997646989 is 989646799.

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 997646989 - 2¹ = 997646987 is a prime.

It is a super-2 number, since 2×997646989² = 1990599029321532242, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (997646987) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 496329 + ... + 498334.

It is an arithmetic number, because the mean of its divisors is an integer number (134279640).

Almost surely, 2^997646989 is an apocalyptic number.

It is an amenable number.

997646989 is a deficient number, since it is larger than the sum of its proper divisors (76590131).

997646989 is a wasteful number, since it uses less digits than its factorization.

997646989 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 994739.

The product of its digits is 52907904, while the sum is 67.

The square root of 997646989 is about 31585.5503197269. The cubic root of 997646989 is about 999.2150470100.

It can be divided in two parts, 9976 and 46989, that added together give a palindrome (56965).

The spelling of 997646989 in words is "nine hundred ninety-seven million, six hundred forty-six thousand, nine hundred eighty-nine".