998985120866 has 4 divisors (see below), whose sum is σ = 1498477681302. Its totient is φ = 499492560432.

The previous prime is 998985120839. The next prime is 998985120869. The reversal of 998985120866 is 668021589899.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 668021589899 = 47 ⋅14213225317.

It can be written as a sum of positive squares in only one way, i.e., 950927274025 + 48057846841 = 975155^2 + 219221^2 .

It is a self number, because there is not a number n which added to its sum of digits gives 998985120866.

It is not an unprimeable number, because it can be changed into a prime (998985120869) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 249746280215 + ... + 249746280218.

Almost surely, 2^998985120866 is an apocalyptic number.

998985120866 is a deficient number, since it is larger than the sum of its proper divisors (499492560436).

998985120866 is a wasteful number, since it uses less digits than its factorization.

998985120866 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 499492560435.

The product of its (nonzero) digits is 134369280, while the sum is 71.

The spelling of 998985120866 in words is "nine hundred ninety-eight billion, nine hundred eighty-five million, one hundred twenty thousand, eight hundred sixty-six".