81544038111904 has 12 divisors (see below), whose sum is σ = 160539825032874. Its totient is φ = 40772019055936.

The previous prime is 81544038111869. The next prime is 81544038111953. The reversal of 81544038111904 is 40911183044518.

It can be written as a sum of positive squares in only one way, i.e., 42912194547600 + 38631843564304 = 6550740^2 + 6215452^2 .

It is a super-3 number, since 3×81544038111904³ (a number of 43 digits) contains 333 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 as a sum of consecutive naturals, namely, 1274125595467 + ... + 1274125595530.

Almost surely, 2^{81544038111904} is an apocalyptic number.

It is an amenable number.

81544038111904 is a deficient number, since it is larger than the sum of its proper divisors (78995786920970).

81544038111904 is a wasteful number, since it uses less digits than its factorization.

81544038111904 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2548251191007 (or 2548251190999 counting only the distinct ones).

The product of its (nonzero) digits is 552960, while the sum is 49.

The spelling of 81544038111904 in words is "eighty-one trillion, five hundred forty-four billion, thirty-eight million, one hundred eleven thousand, nine hundred four".