81037650868 has 12 divisors (see below), whose sum is σ = 142599403492. Its totient is φ = 40294964160.

The previous prime is 81037650847. The next prime is 81037650877. The reversal of 81037650868 is 86805673018.

It can be written as a sum of positive squares in 2 ways, for example, as 27684966544 + 53352684324 = 166388^2 + 230982^2 .

It is a super-2 number, since 2×81037650868² (a number of 23 digits) contains 22 as substring.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 55964505 + ... + 55965952.

Almost surely, 2^81037650868 is an apocalyptic number.

It is an amenable number.

81037650868 is a deficient number, since it is larger than the sum of its proper divisors (61561752624).

81037650868 is a wasteful number, since it uses less digits than its factorization.

81037650868 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 111930642 (or 111930640 counting only the distinct ones).

The product of its (nonzero) digits is 1935360, while the sum is 52.

The spelling of 81037650868 in words is "eighty-one billion, thirty-seven million, six hundred fifty thousand, eight hundred sixty-eight".