81079511 has 16 divisors (see below), whose sum is σ = 87933600. Its totient is φ = 74477568.

The previous prime is 81079501. The next prime is 81079513. The reversal of 81079511 is 11597018.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-81079511 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81079513) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 229511 + ... + 229863.

It is an arithmetic number, because the mean of its divisors is an integer number (5495850).

Almost surely, 2^81079511 is an apocalyptic number.

81079511 is a deficient number, since it is larger than the sum of its proper divisors (6854089).

81079511 is a wasteful number, since it uses less digits than its factorization.

81079511 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 658.

The product of its (nonzero) digits is 2520, while the sum is 32.

The square root of 81079511 is about 9004.4161942904. The cubic root of 81079511 is about 432.8163985043.

The spelling of 81079511 in words is "eighty-one million, seventy-nine thousand, five hundred eleven".