81526307 has 4 divisors (see below), whose sum is σ = 81635616. Its totient is φ = 81417000.

The previous prime is 81526303. The next prime is 81526343. The reversal of 81526307 is 70362518.

It is a happy number.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 70362518 = 2 ⋅35181259.

It is a cyclic number.

It is not a de Polignac number, because 81526307 - 2² = 81526303 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (81526303) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 53528 + ... + 55029.

It is an arithmetic number, because the mean of its divisors is an integer number (20408904).

Almost surely, 2^81526307 is an apocalyptic number.

81526307 is a deficient number, since it is larger than the sum of its proper divisors (109309).

81526307 is a wasteful number, since it uses less digits than its factorization.

81526307 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 109308.

The product of its (nonzero) digits is 10080, while the sum is 32.

The square root of 81526307 is about 9029.1919350516. The cubic root of 81526307 is about 433.6099672816.

The spelling of 81526307 in words is "eighty-one million, five hundred twenty-six thousand, three hundred seven".