1172894561 has 4 divisors (see below), whose sum is σ = 1204594452. Its totient is φ = 1141194672.

The previous prime is 1172894551. The next prime is 1172894573. The reversal of 1172894561 is 1654982711.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 1654982711 = 379 ⋅4366709.

It can be written as a sum of positive squares in 2 ways, for example, as 1034008336 + 138886225 = 32156^2 + 11785^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1172894561 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1172894551) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 15849890 + ... + 15849963.

It is an arithmetic number, because the mean of its divisors is an integer number (301148613).

Almost surely, 2^1172894561 is an apocalyptic number.

It is an amenable number.

1172894561 is a deficient number, since it is larger than the sum of its proper divisors (31699891).

1172894561 is an equidigital number, since it uses as much as digits as its factorization.

1172894561 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 31699890.

The product of its digits is 120960, while the sum is 44.

The square root of 1172894561 is about 34247.5482480133. The cubic root of 1172894561 is about 1054.5964962618.

The spelling of 1172894561 in words is "one billion, one hundred seventy-two million, eight hundred ninety-four thousand, five hundred sixty-one".