998709778 has 32 divisors (see below), whose sum is σ = 1737780480. Its totient is φ = 425429760.

The previous prime is 998709773. The next prime is 998709779. The reversal of 998709778 is 877907899.

998709778 is a nontrivial binomial coefficient, being equal to C(44693, 2).

It is not an unprimeable number, because it can be changed into a prime (998709773) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 83800 + ... + 94972.

It is an arithmetic number, because the mean of its divisors is an integer number (54305640).

Almost surely, 2^998709778 is an apocalyptic number.

998709778 is the 44692-nd triangular number.

998709778 is the 14898-th centered nonagonal number.

998709778 is a deficient number, since it is larger than the sum of its proper divisors (739070702).

998709778 is a wasteful number, since it uses less digits than its factorization.

998709778 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 11442.

The product of its (nonzero) digits is 16003008, while the sum is 64.

The square root of 998709778 is about 31602.3698162021. The cubic root of 998709778 is about 999.5697409037.

The spelling of 998709778 in words is "nine hundred ninety-eight million, seven hundred nine thousand, seven hundred seventy-eight".