15996861 has 12 divisors (see below), whose sum is σ = 23150140. Its totient is φ = 10644480.

The previous prime is 15996811. The next prime is 15996863. The reversal of 15996861 is 16869951.

It can be written as a sum of positive squares in 2 ways, for example, as 5788836 + 10208025 = 2406^2 + 3195^2 .

It is not a de Polignac number, because 15996861 - 2⁷ = 15996733 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (15996863) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 4605 + ... + 7293.

Almost surely, 2^15996861 is an apocalyptic number.

It is an amenable number.

15996861 is a deficient number, since it is larger than the sum of its proper divisors (7153279).

15996861 is a wasteful number, since it uses less digits than its factorization.

15996861 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3356 (or 3353 counting only the distinct ones).

The product of its digits is 116640, while the sum is 45.

The square root of 15996861 is about 3999.6076057533. The cubic root of 15996861 is about 251.9677301838.

It can be divided in two parts, 159 and 96861, that added together give a triangular number (97020 = T₄₄₀).

The spelling of 15996861 in words is "fifteen million, nine hundred ninety-six thousand, eight hundred sixty-one".