81275265 has 16 divisors (see below), whose sum is σ = 144489600. Its totient is φ = 43346736.

The previous prime is 81275263. The next prime is 81275269. The reversal of 81275265 is 56257218.

It is a happy number.

81275265 is a `hidden beast` number, since 8 + 127 + 526 + 5 = 666.

It is not a de Polignac number, because 81275265 - 2¹ = 81275263 is a prime.

It is not an unprimeable number, because it can be changed into a prime (81275263) 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, 300885 + ... + 301154.

It is an arithmetic number, because the mean of its divisors is an integer number (9030600).

Almost surely, 2^81275265 is an apocalyptic number.

It is an amenable number.

81275265 is a deficient number, since it is larger than the sum of its proper divisors (63214335).

81275265 is a wasteful number, since it uses less digits than its factorization.

81275265 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 602053 (or 602047 counting only the distinct ones).

The product of its digits is 33600, while the sum is 36.

The square root of 81275265 is about 9015.2795297761. The cubic root of 81275265 is about 433.1644414149.

The spelling of 81275265 in words is "eighty-one million, two hundred seventy-five thousand, two hundred sixty-five".