81825121934 has 16 divisors (see below), whose sum is σ = 126118267488. Its totient is φ = 39786810912.

The previous prime is 81825121753. The next prime is 81825121943. The reversal of 81825121934 is 43912152818.

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, 129074 + ... + 424629.

It is an arithmetic number, because the mean of its divisors is an integer number (7882391718).

Almost surely, 2^81825121934 is an apocalyptic number.

81825121934 is a deficient number, since it is larger than the sum of its proper divisors (44293145554).

81825121934 is a wasteful number, since it uses less digits than its factorization.

81825121934 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 555739.

The product of its digits is 138240, while the sum is 44.

The spelling of 81825121934 in words is "eighty-one billion, eight hundred twenty-five million, one hundred twenty-one thousand, nine hundred thirty-four".