81368445 has 8 divisors (see below), whose sum is σ = 130189536. Its totient is φ = 43396496.

The previous prime is 81368429. The next prime is 81368467. The reversal of 81368445 is 54486318.

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

It is a cyclic number.

It is not a de Polignac number, because 81368445 - 2⁴ = 81368429 is a prime.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 2712267 + ... + 2712296.

It is an arithmetic number, because the mean of its divisors is an integer number (16273692).

Almost surely, 2^81368445 is an apocalyptic number.

It is an amenable number.

81368445 is a deficient number, since it is larger than the sum of its proper divisors (48821091).

81368445 is a wasteful number, since it uses less digits than its factorization.

81368445 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5424571.

The product of its digits is 92160, while the sum is 39.

The square root of 81368445 is about 9020.4459424133. The cubic root of 81368445 is about 433.3299154892.

The spelling of 81368445 in words is "eighty-one million, three hundred sixty-eight thousand, four hundred forty-five".