81301785 has 8 divisors (see below), whose sum is σ = 130082880. Its totient is φ = 43360944.

The previous prime is 81301783. The next prime is 81301789. The reversal of 81301785 is 58710318.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 81301785 - 2¹ = 81301783 is a prime.

It is not an unprimeable number, because it can be changed into a prime (81301783) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 2710045 + ... + 2710074.

It is an arithmetic number, because the mean of its divisors is an integer number (16260360).

Almost surely, 2^81301785 is an apocalyptic number.

It is an amenable number.

81301785 is a deficient number, since it is larger than the sum of its proper divisors (48781095).

81301785 is a wasteful number, since it uses less digits than its factorization.

81301785 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5420127.

The product of its (nonzero) digits is 6720, while the sum is 33.

The square root of 81301785 is about 9016.7502460698. The cubic root of 81301785 is about 433.2115499325.

The spelling of 81301785 in words is "eighty-one million, three hundred one thousand, seven hundred eighty-five".