11978955 has 32 divisors (see below), whose sum is σ = 21556800. Its totient is φ = 6310656.

The previous prime is 11978921. The next prime is 11978959. The reversal of 11978955 is 55987911.

It is not a de Polignac number, because 11978955 - 2⁹ = 11978443 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (45).

It is a self number, because there is not a number n which added to its sum of digits gives 11978955.

It is not an unprimeable number, because it can be changed into a prime (11978959) by changing a digit.

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 31 ways as a sum of consecutive naturals, for example, 11517 + ... + 12513.

It is an arithmetic number, because the mean of its divisors is an integer number (673650).

Almost surely, 2^11978955 is an apocalyptic number.

11978955 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

11978955 is a deficient number, since it is larger than the sum of its proper divisors (9577845).

11978955 is an equidigital number, since it uses as much as digits as its factorization.

11978955 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1100 (or 1094 counting only the distinct ones).

The product of its digits is 113400, while the sum is 45.

The square root of 11978955 is about 3461.0626980741. The cubic root of 11978955 is about 228.8089340224.

The spelling of 11978955 in words is "eleven million, nine hundred seventy-eight thousand, nine hundred fifty-five".