1156640066 has 4 divisors (see below), whose sum is σ = 1734960102. Its totient is φ = 578320032.

The previous prime is 1156640063. The next prime is 1156640081. The reversal of 1156640066 is 6600466511.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 6600466511 = 79 ⋅83550209.

It can be written as a sum of positive squares in only one way, i.e., 877048225 + 279591841 = 29615^2 + 16721^2 .

It is not an unprimeable number, because it can be changed into a prime (1156640063) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 289160015 + ... + 289160018.

Almost surely, 2^1156640066 is an apocalyptic number.

1156640066 is a deficient number, since it is larger than the sum of its proper divisors (578320036).

1156640066 is an equidigital number, since it uses as much as digits as its factorization.

1156640066 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 578320035.

The product of its (nonzero) digits is 25920, while the sum is 35.

The square root of 1156640066 is about 34009.4114327196. The cubic root of 1156640066 is about 1049.7021274476.

The spelling of 1156640066 in words is "one billion, one hundred fifty-six million, six hundred forty thousand, sixty-six".