111861000021685 has 8 divisors (see below), whose sum is σ = 142129270615896. Its totient is φ = 84224752957440.

The previous prime is 111861000021643. The next prime is 111861000021707. The reversal of 111861000021685 is 586120000168111.

It can be written as a sum of positive squares in 4 ways, for example, as 50823296870116 + 61037703151569 = 7129046^2 + 7812663^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 111861000021685 - 2²⁵ = 111860966467253 is a prime.

It is a Duffinian number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 658005882396 + ... + 658005882565.

It is an arithmetic number, because the mean of its divisors is an integer number (17766158826987).

Almost surely, 2^{111861000021685} is an apocalyptic number.

It is an amenable number.

111861000021685 is a deficient number, since it is larger than the sum of its proper divisors (30268270594211).

111861000021685 is a wasteful number, since it uses less digits than its factorization.

111861000021685 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1316011764983.

The product of its (nonzero) digits is 23040, while the sum is 40.

Adding to 111861000021685 its reverse (586120000168111), we get a palindrome (697981000189796).

The spelling of 111861000021685 in words is "one hundred eleven trillion, eight hundred sixty-one billion, twenty-one thousand, six hundred eighty-five".