989896987 has 2 divisors, whose sum is σ = 989896988. Its totient is φ = 989896986.

The previous prime is 989896949. The next prime is 989897003. The reversal of 989896987 is 789698989.

It is a strong prime.

It is an emirp because it is prime and its reverse (789698989) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 989896987 - 2²⁷ = 855679259 is a prime.

It is an alternating number because its digits alternate between odd and even.

It is not a weakly prime, because it can be changed into another prime (989896387) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 494948493 + 494948494.

It is an arithmetic number, because the mean of its divisors is an integer number (494948494).

Almost surely, 2^989896987 is an apocalyptic number.

989896987 is a deficient number, since it is larger than the sum of its proper divisors (1).

989896987 is an equidigital number, since it uses as much as digits as its factorization.

989896987 is an evil number, because the sum of its binary digits is even.

The product of its digits is 141087744, while the sum is 73.

The square root of 989896987 is about 31462.6284184904. The cubic root of 989896987 is about 996.6209237043.

The spelling of 989896987 in words is "nine hundred eighty-nine million, eight hundred ninety-six thousand, nine hundred eighty-seven".