81037669985 has 8 divisors (see below), whose sum is σ = 98189332800. Its totient is φ = 64200716784.

The previous prime is 81037669963. The next prime is 81037669991. The reversal of 81037669985 is 58996673018.

It is a happy number.

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

It is a cyclic number.

It is not a de Polignac number, because 81037669985 - 2²⁶ = 80970561121 is a prime.

It is a Curzon number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 78676835 + ... + 78677864.

It is an arithmetic number, because the mean of its divisors is an integer number (12273666600).

Almost surely, 2^81037669985 is an apocalyptic number.

It is an amenable number.

81037669985 is a deficient number, since it is larger than the sum of its proper divisors (17151662815).

81037669985 is a wasteful number, since it uses less digits than its factorization.

81037669985 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 157354807.

The product of its (nonzero) digits is 19595520, while the sum is 62.

The spelling of 81037669985 in words is "eighty-one billion, thirty-seven million, six hundred sixty-nine thousand, nine hundred eighty-five".