1166521637 has 2 divisors, whose sum is σ = 1166521638. Its totient is φ = 1166521636.

The previous prime is 1166521561. The next prime is 1166521639. The reversal of 1166521637 is 7361256611.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 1166495716 + 25921 = 34154^2 + 161^2 .

It is an emirp because it is prime and its reverse (7361256611) is a distict prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1166521637 is a prime.

Together with 1166521639, it forms a pair of twin primes.

It is a Chen prime.

It is a self number, because there is not a number n which added to its sum of digits gives 1166521637.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1166521639) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 583260818 + 583260819.

It is an arithmetic number, because the mean of its divisors is an integer number (583260819).

Almost surely, 2^1166521637 is an apocalyptic number.

It is an amenable number.

1166521637 is a deficient number, since it is larger than the sum of its proper divisors (1).

1166521637 is an equidigital number, since it uses as much as digits as its factorization.

1166521637 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 45360, while the sum is 38.

The square root of 1166521637 is about 34154.3794702817. The cubic root of 1166521637 is about 1052.6829759195.

The spelling of 1166521637 in words is "one billion, one hundred sixty-six million, five hundred twenty-one thousand, six hundred thirty-seven".