1186716521 has 4 divisors (see below), whose sum is σ = 1189549200. Its totient is φ = 1183883844.

The previous prime is 1186716493. The next prime is 1186716547. The reversal of 1186716521 is 1256176811.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 1256176811 = 19 ⋅66114569.

It is a cyclic number.

It is not a de Polignac number, because 1186716521 - 2²² = 1182522217 is a prime.

It is a super-2 number, since 2×1186716521² = 2816592202428686882, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1186716551) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1415711 + ... + 1416548.

It is an arithmetic number, because the mean of its divisors is an integer number (297387300).

Almost surely, 2^1186716521 is an apocalyptic number.

It is an amenable number.

1186716521 is a deficient number, since it is larger than the sum of its proper divisors (2832679).

1186716521 is an equidigital number, since it uses as much as digits as its factorization.

1186716521 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2832678.

The product of its digits is 20160, while the sum is 38.

The square root of 1186716521 is about 34448.7520964113. The cubic root of 1186716521 is about 1058.7229550847.

The spelling of 1186716521 in words is "one billion, one hundred eighty-six million, seven hundred sixteen thousand, five hundred twenty-one".