11973978 has 12 divisors (see below), whose sum is σ = 25943658. Its totient is φ = 3991320.

The previous prime is 11973959. The next prime is 11973979. The reversal of 11973978 is 87937911.

It can be written as a sum of positive squares in only one way, i.e., 11716929 + 257049 = 3423^2 + 507^2 .

It is a super-2 number, since 2×11973978² = 286752298288968, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (11973979) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 332593 + ... + 332628.

Almost surely, 2^11973978 is an apocalyptic number.

11973978 is a gapful number since it is divisible by the number (18) formed by its first and last digit.

11973978 is an abundant number, since it is smaller than the sum of its proper divisors (13969680).

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

11973978 is a wasteful number, since it uses less digits than its factorization.

11973978 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 665229 (or 665226 counting only the distinct ones).

The product of its digits is 95256, while the sum is 45.

The square root of 11973978 is about 3460.3436245552. The cubic root of 11973978 is about 228.7772412241. Note that the first 3 decimals are identical.

The spelling of 11973978 in words is "eleven million, nine hundred seventy-three thousand, nine hundred seventy-eight".