81045724 has 6 divisors (see below), whose sum is σ = 141830024. Its totient is φ = 40522860.

The previous prime is 81045707. The next prime is 81045737. The reversal of 81045724 is 42754018.

It is a nialpdrome in base 14.

It is a congruent number.

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 as a sum of consecutive naturals, namely, 10130712 + ... + 10130719.

Almost surely, 2^81045724 is an apocalyptic number.

It is an amenable number.

81045724 is a deficient number, since it is larger than the sum of its proper divisors (60784300).

81045724 is a wasteful number, since it uses less digits than its factorization.

81045724 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 20261435 (or 20261433 counting only the distinct ones).

The product of its (nonzero) digits is 8960, while the sum is 31.

The square root of 81045724 is about 9002.5398638384. The cubic root of 81045724 is about 432.7562698757.

The spelling of 81045724 in words is "eighty-one million, forty-five thousand, seven hundred twenty-four".