1198979978 has 16 divisors (see below), whose sum is σ = 2176300224. Its totient is φ = 483622080.

The previous prime is 1198979953. The next prime is 1198979993. The reversal of 1198979978 is 8799798911.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 2518628 + ... + 2519103.

It is an arithmetic number, because the mean of its divisors is an integer number (136018764).

Almost surely, 2^1198979978 is an apocalyptic number.

1198979978 is a deficient number, since it is larger than the sum of its proper divisors (977320246).

1198979978 is a wasteful number, since it uses less digits than its factorization.

1198979978 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5037757.

The product of its digits is 20575296, while the sum is 68.

The square root of 1198979978 is about 34626.2902719884. The cubic root of 1198979978 is about 1062.3573907421.

The spelling of 1198979978 in words is "one billion, one hundred ninety-eight million, nine hundred seventy-nine thousand, nine hundred seventy-eight".