1166921197 has 4 divisors (see below), whose sum is σ = 1256684380. Its totient is φ = 1077158016.

The previous prime is 1166921179. The next prime is 1166921257. The reversal of 1166921197 is 7911296611.

It is a happy number.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 7911296611 = 38639 ⋅204749.

It can be written as a sum of positive squares in 2 ways, for example, as 201327721 + 965593476 = 14189^2 + 31074^2 .

It is a cyclic number.

It is not a de Polignac number, because 1166921197 - 2⁷ = 1166921069 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1166921177) 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, 44881572 + ... + 44881597.

It is an arithmetic number, because the mean of its divisors is an integer number (314171095).

Almost surely, 2^1166921197 is an apocalyptic number.

It is an amenable number.

1166921197 is a deficient number, since it is larger than the sum of its proper divisors (89763183).

1166921197 is an equidigital number, since it uses as much as digits as its factorization.

1166921197 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 89763182.

The product of its digits is 40824, while the sum is 43.

The square root of 1166921197 is about 34160.2282925627. The cubic root of 1166921197 is about 1052.8031514290.

The spelling of 1166921197 in words is "one billion, one hundred sixty-six million, nine hundred twenty-one thousand, one hundred ninety-seven".