1158789661 has 2 divisors, whose sum is σ = 1158789662. Its totient is φ = 1158789660.

The previous prime is 1158789659. The next prime is 1158789679. The reversal of 1158789661 is 1669878511.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 881733636 + 277056025 = 29694^2 + 16645^2 .

It is a cyclic number.

It is not a de Polignac number, because 1158789661 - 2¹ = 1158789659 is a prime.

Together with 1158789659, it forms a pair of twin primes.

It is a junction number, because it is equal to n+sod(n) for n = 1158789599 and 1158789608.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1158789361) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 579394830 + 579394831.

It is an arithmetic number, because the mean of its divisors is an integer number (579394831).

Almost surely, 2^1158789661 is an apocalyptic number.

It is an amenable number.

1158789661 is a deficient number, since it is larger than the sum of its proper divisors (1).

1158789661 is an equidigital number, since it uses as much as digits as its factorization.

1158789661 is an evil number, because the sum of its binary digits is even.

The product of its digits is 725760, while the sum is 52.

The square root of 1158789661 is about 34040.9997062366. Note that the first 3 decimals coincide. The cubic root of 1158789661 is about 1050.3520092633.

The spelling of 1158789661 in words is "one billion, one hundred fifty-eight million, seven hundred eighty-nine thousand, six hundred sixty-one".