81542735 has 4 divisors (see below), whose sum is σ = 97851288. Its totient is φ = 65234184.

The previous prime is 81542711. The next prime is 81542753. The reversal of 81542735 is 53724518.

It is a happy number.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 81542735 - 2⁸ = 81542479 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 81542695 and 81542704.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 8154269 + ... + 8154278.

It is an arithmetic number, because the mean of its divisors is an integer number (24462822).

Almost surely, 2^81542735 is an apocalyptic number.

81542735 is a deficient number, since it is larger than the sum of its proper divisors (16308553).

81542735 is a wasteful number, since it uses less digits than its factorization.

81542735 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 16308552.

The product of its digits is 33600, while the sum is 35.

The square root of 81542735 is about 9030.1016051870. The cubic root of 81542735 is about 433.6390902580.

The spelling of 81542735 in words is "eighty-one million, five hundred forty-two thousand, seven hundred thirty-five".