81288189635 has 16 divisors (see below), whose sum is σ = 98065080000. Its totient is φ = 64684578816.

The previous prime is 81288189623. The next prime is 81288189637. The reversal of 81288189635 is 53698188218.

It is a cyclic number.

It is not a de Polignac number, because 81288189635 - 2⁶ = 81288189571 is a prime.

It is not an unprimeable number, because it can be changed into a prime (81288189637) 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, 4018667 + ... + 4038843.

It is an arithmetic number, because the mean of its divisors is an integer number (6129067500).

Almost surely, 2^81288189635 is an apocalyptic number.

81288189635 is a deficient number, since it is larger than the sum of its proper divisors (16776890365).

81288189635 is a wasteful number, since it uses less digits than its factorization.

81288189635 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 24430.

The product of its digits is 6635520, while the sum is 59.

The spelling of 81288189635 in words is "eighty-one billion, two hundred eighty-eight million, one hundred eighty-nine thousand, six hundred thirty-five".