989557243 has 2 divisors, whose sum is σ = 989557244. Its totient is φ = 989557242.

The previous prime is 989557207. The next prime is 989557249. The reversal of 989557243 is 342755989.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 989557243 - 2²¹ = 987460091 is a prime.

It is a super-2 number, since 2×989557243² = 1958447074347522098, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (989557249) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 494778621 + 494778622.

It is an arithmetic number, because the mean of its divisors is an integer number (494778622).

Almost surely, 2^989557243 is an apocalyptic number.

989557243 is a deficient number, since it is larger than the sum of its proper divisors (1).

989557243 is an equidigital number, since it uses as much as digits as its factorization.

989557243 is an evil number, because the sum of its binary digits is even.

The product of its digits is 2721600, while the sum is 52.

The square root of 989557243 is about 31457.2287876730. The cubic root of 989557243 is about 996.5068934138.

The spelling of 989557243 in words is "nine hundred eighty-nine million, five hundred fifty-seven thousand, two hundred forty-three".