1000000998978 has 32 divisors (see below), whose sum is σ = 2027820662784. Its totient is φ = 328728656592.

The previous prime is 1000000998961. The next prime is 1000000998979. The reversal of 1000000998978 is 8798990000001.

It is a self number, because there is not a number n which added to its sum of digits gives 1000000998978.

It is not an unprimeable number, because it can be changed into a prime (1000000998979) 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, 3801900 + ... + 4056407.

It is an arithmetic number, because the mean of its divisors is an integer number (63369395712).

Almost surely, 2^{1000000998978} is an apocalyptic number.

1000000998978 is an abundant number, since it is smaller than the sum of its proper divisors (1027819663806).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

1000000998978 is a wasteful number, since it uses less digits than its factorization.

1000000998978 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7858606.

The product of its (nonzero) digits is 326592, while the sum is 51.

Adding to 1000000998978 its reverse (8798990000001), we get a palindrome (9798990998979).

The spelling of 1000000998978 in words is "one trillion, nine hundred ninety-eight thousand, nine hundred seventy-eight".