81071000 has 32 divisors (see below), whose sum is σ = 189708480. Its totient is φ = 32428000.

The previous prime is 81070963. The next prime is 81071009. The reversal of 81071000 is 17018.

It is a self number, because there is not a number n which added to its sum of digits gives 81071000.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81071009) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 39536 + ... + 41535.

It is an arithmetic number, because the mean of its divisors is an integer number (5928390).

Almost surely, 2^81071000 is an apocalyptic number.

It is an amenable number.

81071000 is an abundant number, since it is smaller than the sum of its proper divisors (108637480).

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

81071000 is a wasteful number, since it uses less digits than its factorization.

81071000 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 81092 (or 81078 counting only the distinct ones).

The product of its (nonzero) digits is 56, while the sum is 17.

The square root of 81071000 is about 9003.9435804541. The cubic root of 81071000 is about 432.8012535796.

Adding to 81071000 its reverse (17018), we get a palindrome (81088018).

The spelling of 81071000 in words is "eighty-one million, seventy-one thousand".