1191431955 has 32 divisors (see below), whose sum is σ = 2293286400. Its totient is φ = 515987712.

The previous prime is 1191431951. The next prime is 1191431971. The reversal of 1191431955 is 5591341911.

It is not a de Polignac number, because 1191431955 - 2² = 1191431951 is a prime.

It is not an unprimeable number, because it can be changed into a prime (1191431951) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 296610 + ... + 300599.

It is an arithmetic number, because the mean of its divisors is an integer number (71665200).

Almost surely, 2^1191431955 is an apocalyptic number.

1191431955 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

1191431955 is a deficient number, since it is larger than the sum of its proper divisors (1101854445).

1191431955 is a wasteful number, since it uses less digits than its factorization.

1191431955 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 597243.

The product of its digits is 24300, while the sum is 39.

The square root of 1191431955 is about 34517.1255321181. The cubic root of 1191431955 is about 1060.1233851270.

The spelling of 1191431955 in words is "one billion, one hundred ninety-one million, four hundred thirty-one thousand, nine hundred fifty-five".