1686281723661 has 16 divisors (see below), whose sum is σ = 2269131972800. Its totient is φ = 1113810818688.

The previous prime is 1686281723653. The next prime is 1686281723671. The reversal of 1686281723661 is 1663271826861.

It is not a de Polignac number, because 1686281723661 - 2³ = 1686281723653 is a prime.

It is a super-2 number, since 2×1686281723661² (a number of 25 digits) contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1686281723611) 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, 6006105 + ... + 6280593.

It is an arithmetic number, because the mean of its divisors is an integer number (141820748300).

Almost surely, 2^{1686281723661} is an apocalyptic number.

It is an amenable number.

1686281723661 is a deficient number, since it is larger than the sum of its proper divisors (582850249139).

1686281723661 is a wasteful number, since it uses less digits than its factorization.

1686281723661 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 293388.

The product of its digits is 6967296, while the sum is 57.

The spelling of 1686281723661 in words is "one trillion, six hundred eighty-six billion, two hundred eighty-one million, seven hundred twenty-three thousand, six hundred sixty-one".