81985627476650 has 48 divisors (see below), whose sum is σ = 156369301646040. Its totient is φ = 31962299750400.

The previous prime is 81985627476637. The next prime is 81985627476659. The reversal of 81985627476650 is 5667472658918.

It can be written as a sum of positive squares in 12 ways, for example, as 291199457641 + 81694428019009 = 539629^2 + 9038497^2 .

It is a super-2 number, since 2×81985627476650² (a number of 29 digits) contains 22 as substring.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (81985627476659) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 18012815 + ... + 22100514.

Almost surely, 2^{81985627476650} is an apocalyptic number.

81985627476650 is a deficient number, since it is larger than the sum of its proper divisors (74383674169390).

81985627476650 is a wasteful number, since it uses less digits than its factorization.

81985627476650 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 40114379 (or 40114374 counting only the distinct ones).

The product of its (nonzero) digits is 1219276800, while the sum is 74.

The spelling of 81985627476650 in words is "eighty-one trillion, nine hundred eighty-five billion, six hundred twenty-seven million, four hundred seventy-six thousand, six hundred fifty".