15661071 has 6 divisors (see below), whose sum is σ = 22621560. Its totient is φ = 10440708.

The previous prime is 15661069. The next prime is 15661099. The reversal of 15661071 is 17016651.

It is not a de Polignac number, because 15661071 - 2¹ = 15661069 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (15661031) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 870051 + ... + 870068.

It is an arithmetic number, because the mean of its divisors is an integer number (3770260).

Almost surely, 2^15661071 is an apocalyptic number.

15661071 is a deficient number, since it is larger than the sum of its proper divisors (6960489).

15661071 is a wasteful number, since it uses less digits than its factorization.

15661071 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1740125 (or 1740122 counting only the distinct ones).

The product of its (nonzero) digits is 1260, while the sum is 27.

The square root of 15661071 is about 3957.4071056691. The cubic root of 15661071 is about 250.1922308180.

The spelling of 15661071 in words is "fifteen million, six hundred sixty-one thousand, seventy-one".