1172538891 has 12 divisors (see below), whose sum is σ = 1694406168. Its totient is φ = 781351584.

The previous prime is 1172538863. The next prime is 1172538911. The reversal of 1172538891 is 1988352711.

It is not a de Polignac number, because 1172538891 - 2⁵ = 1172538859 is a prime.

It is not an unprimeable number, because it can be changed into a prime (1172538821) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 5685 + ... + 48758.

It is an arithmetic number, because the mean of its divisors is an integer number (141200514).

Almost surely, 2^1172538891 is an apocalyptic number.

1172538891 is a deficient number, since it is larger than the sum of its proper divisors (521867277).

1172538891 is a wasteful number, since it uses less digits than its factorization.

1172538891 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 56842 (or 56839 counting only the distinct ones).

The product of its digits is 120960, while the sum is 45.

The square root of 1172538891 is about 34242.3552198151. The cubic root of 1172538891 is about 1054.4898864355.

The spelling of 1172538891 in words is "one billion, one hundred seventy-two million, five hundred thirty-eight thousand, eight hundred ninety-one".