15696661 has 4 divisors (see below), whose sum is σ = 16620012. Its totient is φ = 14773312.

The previous prime is 15696647. The next prime is 15696673. The reversal of 15696661 is 16669651.

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 8439025 + 7257636 = 2905^2 + 2694^2 .

It is a cyclic number.

It is not a de Polignac number, because 15696661 - 2¹⁹ = 15172373 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 (15696631) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 461650 + ... + 461683.

It is an arithmetic number, because the mean of its divisors is an integer number (4155003).

Almost surely, 2^15696661 is an apocalyptic number.

It is an amenable number.

15696661 is a deficient number, since it is larger than the sum of its proper divisors (923351).

15696661 is an equidigital number, since it uses as much as digits as its factorization.

15696661 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 923350.

The product of its digits is 58320, while the sum is 40.

The square root of 15696661 is about 3961.9011850373. The cubic root of 15696661 is about 250.3816092013.

The spelling of 15696661 in words is "fifteen million, six hundred ninety-six thousand, six hundred sixty-one".