11979978 has 16 divisors (see below), whose sum is σ = 24001920. Its totient is φ = 3986336.

The previous prime is 11979967. The next prime is 11979983. The reversal of 11979978 is 87997911.

It is a self number, because there is not a number n which added to its sum of digits gives 11979978.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 2926 + ... + 5702.

It is an arithmetic number, because the mean of its divisors is an integer number (1500120).

Almost surely, 2^11979978 is an apocalyptic number.

11979978 is an abundant number, since it is smaller than the sum of its proper divisors (12021942).

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

11979978 is a wasteful number, since it uses less digits than its factorization.

11979978 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3501.

The product of its digits is 285768, while the sum is 51.

The square root of 11979978 is about 3461.2104818979. The cubic root of 11979978 is about 228.8154472471.

It can be divided in two parts, 1197 and 9978, that added together give a triangular number (11175 = T₁₄₉).

The spelling of 11979978 in words is "eleven million, nine hundred seventy-nine thousand, nine hundred seventy-eight".