81045607 has 4 divisors (see below), whose sum is σ = 81111240. Its totient is φ = 80979976.

The previous prime is 81045589. The next prime is 81045631. The reversal of 81045607 is 70654018.

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 81045607 - 2¹⁵ = 81012839 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 (81045677) by changing a digit.

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 3 ways as a sum of consecutive naturals, for example, 30928 + ... + 33445.

It is an arithmetic number, because the mean of its divisors is an integer number (20277810).

Almost surely, 2^81045607 is an apocalyptic number.

81045607 is a deficient number, since it is larger than the sum of its proper divisors (65633).

81045607 is a wasteful number, since it uses less digits than its factorization.

81045607 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 65632.

The product of its (nonzero) digits is 6720, while the sum is 31.

The square root of 81045607 is about 9002.5333656699. The cubic root of 81045607 is about 432.7560616291.

The spelling of 81045607 in words is "eighty-one million, forty-five thousand, six hundred seven".