81701025 has 24 divisors (see below), whose sum is σ = 154377024. Its totient is φ = 37348800.

The previous prime is 81700937. The next prime is 81701029. The reversal of 81701025 is 52010718.

It is not a de Polignac number, because 81701025 - 2¹⁸ = 81438881 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 81700986 and 81701004.

It is not an unprimeable number, because it can be changed into a prime (81701029) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 77286 + ... + 78335.

It is an arithmetic number, because the mean of its divisors is an integer number (6432376).

Almost surely, 2^81701025 is an apocalyptic number.

It is an amenable number.

81701025 is a deficient number, since it is larger than the sum of its proper divisors (72675999).

81701025 is a wasteful number, since it uses less digits than its factorization.

81701025 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 155641 (or 155636 counting only the distinct ones).

The product of its (nonzero) digits is 560, while the sum is 24.

The square root of 81701025 is about 9038.8619305751. The cubic root of 81701025 is about 433.9195009511.

The spelling of 81701025 in words is "eighty-one million, seven hundred one thousand, twenty-five".