81735847 has 12 divisors (see below), whose sum is σ = 87448336. Its totient is φ = 76377600.

The previous prime is 81735817. The next prime is 81735877. The reversal of 81735847 is 74853718.

It is an interprime number because it is at equal distance from previous prime (81735817) and next prime (81735877).

It is a de Polignac number, because none of the positive numbers 2^k-81735847 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81735817) 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, 42703 + ... + 44575.

Almost surely, 2^81735847 is an apocalyptic number.

81735847 is a deficient number, since it is larger than the sum of its proper divisors (5712489).

81735847 is a wasteful number, since it uses less digits than its factorization.

81735847 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2058 (or 2041 counting only the distinct ones).

The product of its digits is 188160, while the sum is 43.

The square root of 81735847 is about 9040.7879634465. The cubic root of 81735847 is about 433.9811395033.

The spelling of 81735847 in words is "eighty-one million, seven hundred thirty-five thousand, eight hundred forty-seven".