81121495174 has 16 divisors (see below), whose sum is σ = 122591358288. Its totient is φ = 40257810432.

The previous prime is 81121495159. The next prime is 81121495187. The reversal of 81121495174 is 47159412118.

It is a self number, because there is not a number n which added to its sum of digits gives 81121495174.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1831174 + ... + 1874950.

It is an arithmetic number, because the mean of its divisors is an integer number (7661959893).

Almost surely, 2^81121495174 is an apocalyptic number.

81121495174 is a deficient number, since it is larger than the sum of its proper divisors (41469863114).

81121495174 is a wasteful number, since it uses less digits than its factorization.

81121495174 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 50679.

The product of its digits is 80640, while the sum is 43.

The spelling of 81121495174 in words is "eighty-one billion, one hundred twenty-one million, four hundred ninety-five thousand, one hundred seventy-four".