81242307 has 12 divisors (see below), whose sum is σ = 117461344. Its totient is φ = 54110160.

The previous prime is 81242299. The next prime is 81242321. The reversal of 81242307 is 70324218.

It is not a de Polignac number, because 81242307 - 2³ = 81242299 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (81240307) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 7413 + ... + 14745.

Almost surely, 2^81242307 is an apocalyptic number.

81242307 is a deficient number, since it is larger than the sum of its proper divisors (36219037).

81242307 is a wasteful number, since it uses less digits than its factorization.

81242307 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8570 (or 8567 counting only the distinct ones).

The product of its (nonzero) digits is 2688, while the sum is 27.

The square root of 81242307 is about 9013.4514476975. The cubic root of 81242307 is about 433.1058825417.

The spelling of 81242307 in words is "eighty-one million, two hundred forty-two thousand, three hundred seven".