81038203641 has 12 divisors (see below), whose sum is σ = 119777397168. Its totient is φ = 52769062584.

The previous prime is 81038203633. The next prime is 81038203663. The reversal of 81038203641 is 14630283018.

81038203641 is a `hidden beast` number, since 8 + 1 + 0 + 3 + 8 + 2 + 0 + 3 + 641 = 666.

It is not a de Polignac number, because 81038203641 - 2³ = 81038203633 is a prime.

It is a Smith number, since the sum of its digits (36) coincides with the sum of the digits of its prime factors.

It is a junction number, because it is equal to n+sod(n) for n = 81038203596 and 81038203605.

It is not an unprimeable number, because it can be changed into a prime (81038203681) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 104700135 + ... + 104700908.

It is an arithmetic number, because the mean of its divisors is an integer number (9981449764).

Almost surely, 2^81038203641 is an apocalyptic number.

It is an amenable number.

81038203641 is a deficient number, since it is larger than the sum of its proper divisors (38739193527).

81038203641 is a wasteful number, since it uses less digits than its factorization.

81038203641 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 209401092 (or 209401089 counting only the distinct ones).

The product of its (nonzero) digits is 27648, while the sum is 36.

Adding to 81038203641 its reverse (14630283018), we get a palindrome (95668486659).

The spelling of 81038203641 in words is "eighty-one billion, thirty-eight million, two hundred three thousand, six hundred forty-one".