997643747 has 2 divisors, whose sum is σ = 997643748. Its totient is φ = 997643746.

The previous prime is 997643741. The next prime is 997643831. The reversal of 997643747 is 747346799.

It is a happy number.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 997643747 - 2¹⁴ = 997627363 is a prime.

It is a Chen prime.

It is a junction number, because it is equal to n+sod(n) for n = 997643692 and 997643701.

It is not a weakly prime, because it can be changed into another prime (997643741) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 498821873 + 498821874.

It is an arithmetic number, because the mean of its divisors is an integer number (498821874).

Almost surely, 2^997643747 is an apocalyptic number.

997643747 is a deficient number, since it is larger than the sum of its proper divisors (1).

997643747 is an equidigital number, since it uses as much as digits as its factorization.

997643747 is an evil number, because the sum of its binary digits is even.

The product of its digits is 8001504, while the sum is 56.

The square root of 997643747 is about 31585.4989987494. The cubic root of 997643747 is about 999.2139646436.

The spelling of 997643747 in words is "nine hundred ninety-seven million, six hundred forty-three thousand, seven hundred forty-seven".