81272307 has 8 divisors (see below), whose sum is σ = 108405184. Its totient is φ = 54160488.

The previous prime is 81272299. The next prime is 81272311. The reversal of 81272307 is 70327218.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 81272307 - 2³ = 81272299 is a prime.

It is an alternating number because its digits alternate between even and odd.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (81272357) 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, 10428 + ... + 16470.

It is an arithmetic number, because the mean of its divisors is an integer number (13550648).

Almost surely, 2^81272307 is an apocalyptic number.

81272307 is a deficient number, since it is larger than the sum of its proper divisors (27132877).

81272307 is a wasteful number, since it uses less digits than its factorization.

81272307 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10529.

The product of its (nonzero) digits is 4704, while the sum is 30.

The square root of 81272307 is about 9015.1154734701. The cubic root of 81272307 is about 433.1591863681.

The spelling of 81272307 in words is "eighty-one million, two hundred seventy-two thousand, three hundred seven".