2686885721 has 16 divisors (see below), whose sum is σ = 3027873744. Its totient is φ = 2367615744.

The previous prime is 2686885687. The next prime is 2686885753. The reversal of 2686885721 is 1275886862.

It can be written as a sum of positive squares in 8 ways, for example, as 18496 + 2686867225 = 136^2 + 51835^2 .

It is a de Polignac number, because none of the positive numbers 2^k-2686885721 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (53).

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (2686881721) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 27206 + ... + 78191.

It is an arithmetic number, because the mean of its divisors is an integer number (189242109).

Almost surely, 2^2686885721 is an apocalyptic number.

It is an amenable number.

2686885721 is a deficient number, since it is larger than the sum of its proper divisors (340988023).

2686885721 is a wasteful number, since it uses less digits than its factorization.

2686885721 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 105500.

The product of its digits is 2580480, while the sum is 53.

The square root of 2686885721 is about 51835.1784119627. The cubic root of 2686885721 is about 1390.2185052352.

The spelling of 2686885721 in words is "two billion, six hundred eighty-six million, eight hundred eighty-five thousand, seven hundred twenty-one".