997890559 has 2 divisors, whose sum is σ = 997890560. Its totient is φ = 997890558.

The previous prime is 997890547. The next prime is 997890613. The reversal of 997890559 is 955098799.

It is a happy number.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 997890559 - 2¹³ = 997882367 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 997890497 and 997890506.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (997890539) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 498945279 + 498945280.

It is an arithmetic number, because the mean of its divisors is an integer number (498945280).

Almost surely, 2^997890559 is an apocalyptic number.

997890559 is a deficient number, since it is larger than the sum of its proper divisors (1).

997890559 is an equidigital number, since it uses as much as digits as its factorization.

997890559 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 9185400, while the sum is 61.

The square root of 997890559 is about 31589.4058032119. The cubic root of 997890559 is about 999.2963580041.

The spelling of 997890559 in words is "nine hundred ninety-seven million, eight hundred ninety thousand, five hundred fifty-nine".