81402177657824 has 24 divisors (see below), whose sum is σ = 164169330858288. Its totient is φ = 39708379344640.

The previous prime is 81402177657803. The next prime is 81402177657833. The reversal of 81402177657824 is 42875677120418.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 31022170052 + ... + 31022172675.

It is an arithmetic number, because the mean of its divisors is an integer number (6840388785762).

Almost surely, 2^{81402177657824} is an apocalyptic number.

It is an amenable number.

81402177657824 is an abundant number, since it is smaller than the sum of its proper divisors (82767153200464).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

81402177657824 is a wasteful number, since it uses less digits than its factorization.

81402177657824 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 62044342778 (or 62044342770 counting only the distinct ones).

The product of its (nonzero) digits is 42147840, while the sum is 62.

The spelling of 81402177657824 in words is "eighty-one trillion, four hundred two billion, one hundred seventy-seven million, six hundred fifty-seven thousand, eight hundred twenty-four".