1147747561 has 4 divisors (see below), whose sum is σ = 1151891332. Its totient is φ = 1143603792.

The previous prime is 1147747547. The next prime is 1147747577. The reversal of 1147747561 is 1657477411.

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 758671936 + 389075625 = 27544^2 + 19725^2 .

It is a cyclic number.

It is not a de Polignac number, because 1147747561 - 2¹⁵ = 1147714793 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1147744561) 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, 2071470 + ... + 2072023.

It is an arithmetic number, because the mean of its divisors is an integer number (287972833).

Almost surely, 2^1147747561 is an apocalyptic number.

It is an amenable number.

1147747561 is a deficient number, since it is larger than the sum of its proper divisors (4143771).

1147747561 is an equidigital number, since it uses as much as digits as its factorization.

1147747561 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4143770.

The product of its digits is 164640, while the sum is 43.

The square root of 1147747561 is about 33878.4232366266. The cubic root of 1147747561 is about 1047.0050896373.

The spelling of 1147747561 in words is "one billion, one hundred forty-seven million, seven hundred forty-seven thousand, five hundred sixty-one".