998601881 has 2 divisors, whose sum is σ = 998601882. Its totient is φ = 998601880.

The previous prime is 998601869. The next prime is 998601907. The reversal of 998601881 is 188106899.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 782041225 + 216560656 = 27965^2 + 14716^2 .

It is an emirp because it is prime and its reverse (188106899) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 998601881 - 2¹⁰ = 998600857 is a prime.

It is a super-2 number, since 2×998601881² = 1994411433473476322, which contains 22 as substring.

It is a Sophie Germain prime.

It is a Chen prime.

It is a Curzon number.

It is not a weakly prime, because it can be changed into another prime (998601841) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 499300940 + 499300941.

It is an arithmetic number, because the mean of its divisors is an integer number (499300941).

Almost surely, 2^998601881 is an apocalyptic number.

It is an amenable number.

998601881 is a deficient number, since it is larger than the sum of its proper divisors (1).

998601881 is an equidigital number, since it uses as much as digits as its factorization.

998601881 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 248832, while the sum is 50.

The square root of 998601881 is about 31600.6626671024. The cubic root of 998601881 is about 999.5337429715.

The spelling of 998601881 in words is "nine hundred ninety-eight million, six hundred one thousand, eight hundred eighty-one".