79729081 has 2 divisors, whose sum is σ = 79729082. Its totient is φ = 79729080.

The previous prime is 79729049. The next prime is 79729087. The reversal of 79729081 is 18092797.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 55875625 + 23853456 = 7475^2 + 4884^2 .

It is an emirp because it is prime and its reverse (18092797) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 79729081 - 2⁵ = 79729049 is a prime.

It is a super-2 number, since 2×79729081² = 12713452714209122, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (79729087) 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 as a sum of consecutive naturals, namely, 39864540 + 39864541.

It is an arithmetic number, because the mean of its divisors is an integer number (39864541).

Almost surely, 2^79729081 is an apocalyptic number.

It is an amenable number.

79729081 is a deficient number, since it is larger than the sum of its proper divisors (1).

79729081 is an equidigital number, since it uses as much as digits as its factorization.

79729081 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 63504, while the sum is 43.

The square root of 79729081 is about 8929.1142337860. The cubic root of 79729081 is about 430.3999901679.

The spelling of 79729081 in words is "seventy-nine million, seven hundred twenty-nine thousand, eighty-one".