1161600661 has 4 divisors (see below), whose sum is σ = 1250954572. Its totient is φ = 1072246752.

The previous prime is 1161600653. The next prime is 1161600733. The reversal of 1161600661 is 1660061611.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 546858225 + 614742436 = 23385^2 + 24794^2 .

It is a cyclic number.

It is not a de Polignac number, because 1161600661 - 2³ = 1161600653 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 (1161600061) 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, 44676936 + ... + 44676961.

It is an arithmetic number, because the mean of its divisors is an integer number (312738643).

Almost surely, 2^1161600661 is an apocalyptic number.

It is an amenable number.

1161600661 is a deficient number, since it is larger than the sum of its proper divisors (89353911).

1161600661 is an equidigital number, since it uses as much as digits as its factorization.

1161600661 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 89353910.

The product of its (nonzero) digits is 1296, while the sum is 28.

The square root of 1161600661 is about 34082.2631437526. The cubic root of 1161600661 is about 1051.2006404916.

The spelling of 1161600661 in words is "one billion, one hundred sixty-one million, six hundred thousand, six hundred sixty-one".