81335730 has 32 divisors (see below), whose sum is σ = 223092864. Its totient is φ = 18590976.

The previous prime is 81335719. The next prime is 81335741. The reversal of 81335730 is 3753318.

It is an interprime number because it is at equal distance from previous prime (81335719) and next prime (81335741).

It is a Harshad number since it is a multiple of its sum of digits (30).

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 193447 + ... + 193866.

It is an arithmetic number, because the mean of its divisors is an integer number (6971652).

Almost surely, 2^81335730 is an apocalyptic number.

81335730 is an abundant number, since it is smaller than the sum of its proper divisors (141757134).

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

81335730 is a wasteful number, since it uses less digits than its factorization.

81335730 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 387330.

The product of its (nonzero) digits is 7560, while the sum is 30.

The square root of 81335730 is about 9018.6323796904. The cubic root of 81335730 is about 433.2718328236.

The spelling of 81335730 in words is "eighty-one million, three hundred thirty-five thousand, seven hundred thirty".