11978091 has 16 divisors (see below), whose sum is σ = 18124800. Its totient is φ = 7814664.

The previous prime is 11978077. The next prime is 11978107. The reversal of 11978091 is 19087911.

It is not a de Polignac number, because 11978091 - 2⁹ = 11977579 is a prime.

It is not an unprimeable number, because it can be changed into a prime (11978041) 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, 3451 + ... + 5988.

It is an arithmetic number, because the mean of its divisors is an integer number (1132800).

Almost surely, 2^11978091 is an apocalyptic number.

11978091 is a deficient number, since it is larger than the sum of its proper divisors (6146709).

11978091 is an equidigital number, since it uses as much as digits as its factorization.

11978091 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9495 (or 9489 counting only the distinct ones).

The product of its (nonzero) digits is 4536, while the sum is 36.

The square root of 11978091 is about 3460.9378786682. The cubic root of 11978091 is about 228.8034328283.

It can be divided in two parts, 119 and 78091, that added together give a triangular number (78210 = T₃₉₅).

The spelling of 11978091 in words is "eleven million, nine hundred seventy-eight thousand, ninety-one".