81500271 has 16 divisors (see below), whose sum is σ = 113602560. Its totient is φ = 51910560.

The previous prime is 81500219. The next prime is 81500297. The reversal of 81500271 is 17200518.

It is not a de Polignac number, because 81500271 - 2⁷ = 81500143 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81500171) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1801 + ... + 12893.

It is an arithmetic number, because the mean of its divisors is an integer number (7100160).

Almost surely, 2^81500271 is an apocalyptic number.

81500271 is a deficient number, since it is larger than the sum of its proper divisors (32102289).

81500271 is a wasteful number, since it uses less digits than its factorization.

81500271 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 11206.

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

The square root of 81500271 is about 9027.7500519232. The cubic root of 81500271 is about 433.5638035687.

Adding to 81500271 its reverse (17200518), we get a palindrome (98700789).

The spelling of 81500271 in words is "eighty-one million, five hundred thousand, two hundred seventy-one".