81537042 has 16 divisors (see below), whose sum is σ = 165039840. Its totient is φ = 26851392.

The previous prime is 81537041. The next prime is 81537059. The reversal of 81537042 is 24073518.

It is not an unprimeable number, because it can be changed into a prime (81537041) 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, 81367 + ... + 82362.

It is an arithmetic number, because the mean of its divisors is an integer number (10314990).

Almost surely, 2^81537042 is an apocalyptic number.

81537042 is an abundant number, since it is smaller than the sum of its proper divisors (83502798).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

81537042 is a wasteful number, since it uses less digits than its factorization.

81537042 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 163817.

The product of its (nonzero) digits is 6720, while the sum is 30.

The square root of 81537042 is about 9029.7863762107. The cubic root of 81537042 is about 433.6289983522.

The spelling of 81537042 in words is "eighty-one million, five hundred thirty-seven thousand, forty-two".