81176501690 has 16 divisors (see below), whose sum is σ = 148594275360. Its totient is φ = 31920251280.

The previous prime is 81176501689. The next prime is 81176501711. The reversal of 81176501690 is 9610567118.

It is a super-2 number, since 2×81176501690² (a number of 23 digits) contains 22 as substring.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 68793056 + ... + 68794235.

It is an arithmetic number, because the mean of its divisors is an integer number (9287142210).

Almost surely, 2^81176501690 is an apocalyptic number.

81176501690 is a deficient number, since it is larger than the sum of its proper divisors (67417773670).

81176501690 is a wasteful number, since it uses less digits than its factorization.

81176501690 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 137587357.

The product of its (nonzero) digits is 90720, while the sum is 44.

The spelling of 81176501690 in words is "eighty-one billion, one hundred seventy-six million, five hundred one thousand, six hundred ninety".