1191345978 has 32 divisors (see below), whose sum is σ = 2456951616. Its totient is φ = 384919808.

The previous prime is 1191345977. The next prime is 1191345997. The reversal of 1191345978 is 8795431911.

It is not an unprimeable number, because it can be changed into a prime (1191345971) 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, 3826 + ... + 48962.

It is an arithmetic number, because the mean of its divisors is an integer number (76779738).

Almost surely, 2^1191345978 is an apocalyptic number.

1191345978 is an abundant number, since it is smaller than the sum of its proper divisors (1265605638).

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

1191345978 is a wasteful number, since it uses less digits than its factorization.

1191345978 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 45278.

The product of its digits is 272160, while the sum is 48.

The square root of 1191345978 is about 34515.8800843901. The cubic root of 1191345978 is about 1060.0978840425.

The spelling of 1191345978 in words is "one billion, one hundred ninety-one million, three hundred forty-five thousand, nine hundred seventy-eight".