1147240261 has 4 divisors (see below), whose sum is σ = 1186800300. Its totient is φ = 1107680224.

The previous prime is 1147240231. The next prime is 1147240277. The reversal of 1147240261 is 1620427411.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 1620427411 = 1429 ⋅1133959.

It can be written as a sum of positive squares in 2 ways, for example, as 763472161 + 383768100 = 27631^2 + 19590^2 .

It is a cyclic number.

It is not a de Polignac number, because 1147240261 - 2¹³ = 1147232069 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 (1147240231) 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, 19779976 + ... + 19780033.

It is an arithmetic number, because the mean of its divisors is an integer number (296700075).

Almost surely, 2^1147240261 is an apocalyptic number.

It is an amenable number.

1147240261 is a deficient number, since it is larger than the sum of its proper divisors (39560039).

1147240261 is an equidigital number, since it uses as much as digits as its factorization.

1147240261 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 39560038.

The product of its (nonzero) digits is 2688, while the sum is 28.

The square root of 1147240261 is about 33870.9353428570. The cubic root of 1147240261 is about 1046.8508094994.

Adding to 1147240261 its reverse (1620427411), we get a palindrome (2767667672).

The spelling of 1147240261 in words is "one billion, one hundred forty-seven million, two hundred forty thousand, two hundred sixty-one".