81189950568403 has 4 divisors (see below), whose sum is σ = 81192733076440. Its totient is φ = 81187168060368.

The previous prime is 81189950568401. The next prime is 81189950568413. The reversal of 81189950568403 is 30486505998118.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 81189950568403 - 2¹ = 81189950568401 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (81189950568401) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1391210250 + ... + 1391268607.

It is an arithmetic number, because the mean of its divisors is an integer number (20298183269110).

Almost surely, 2^{81189950568403} is an apocalyptic number.

81189950568403 is a deficient number, since it is larger than the sum of its proper divisors (2782508037).

81189950568403 is a wasteful number, since it uses less digits than its factorization.

81189950568403 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2782508036.

The product of its (nonzero) digits is 74649600, while the sum is 67.

The spelling of 81189950568403 in words is "eighty-one trillion, one hundred eighty-nine billion, nine hundred fifty million, five hundred sixty-eight thousand, four hundred three".