1156506661 has 16 divisors (see below), whose sum is σ = 1190893248. Its totient is φ = 1122768000.

The previous prime is 1156506647. The next prime is 1156506667. The reversal of 1156506661 is 1666056511.

It is a cyclic number.

It is not a de Polignac number, because 1156506661 - 2¹⁷ = 1156375589 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 1156506661.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1156506667) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1673326 + ... + 1674016.

It is an arithmetic number, because the mean of its divisors is an integer number (74430828).

Almost surely, 2^1156506661 is an apocalyptic number.

It is an amenable number.

1156506661 is a deficient number, since it is larger than the sum of its proper divisors (34386587).

1156506661 is a wasteful number, since it uses less digits than its factorization.

1156506661 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1092.

The product of its (nonzero) digits is 32400, while the sum is 37.

The square root of 1156506661 is about 34007.4500808279. The cubic root of 1156506661 is about 1049.6617689124.

The spelling of 1156506661 in words is "one billion, one hundred fifty-six million, five hundred six thousand, six hundred sixty-one".