81725125429 has 24 divisors (see below), whose sum is σ = 90355521600. Its totient is φ = 73767462912.

The previous prime is 81725125421. The next prime is 81725125441. The reversal of 81725125429 is 92452152718.

It is not a de Polignac number, because 81725125429 - 2³ = 81725125421 is a prime.

It is a super-2 number, since 2×81725125429² (a number of 23 digits) contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81725125421) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 2114722 + ... + 2153020.

It is an arithmetic number, because the mean of its divisors is an integer number (3764813400).

Almost surely, 2^81725125429 is an apocalyptic number.

It is an amenable number.

81725125429 is a deficient number, since it is larger than the sum of its proper divisors (8630396171).

81725125429 is a wasteful number, since it uses less digits than its factorization.

81725125429 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 38617 (or 38598 counting only the distinct ones).

The product of its digits is 403200, while the sum is 46.

The spelling of 81725125429 in words is "eighty-one billion, seven hundred twenty-five million, one hundred twenty-five thousand, four hundred twenty-nine".