89728724081 has 2 divisors, whose sum is σ = 89728724082. Its totient is φ = 89728724080.

The previous prime is 89728724023. The next prime is 89728724191. The reversal of 89728724081 is 18042782798.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 84167293456 + 5561430625 = 290116^2 + 74575^2 .

It is a cyclic number.

It is not a de Polignac number, because 89728724081 - 2⁶ = 89728724017 is a prime.

It is a super-2 number, since 2×89728724081² (a number of 23 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (89728724381) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 44864362040 + 44864362041.

It is an arithmetic number, because the mean of its divisors is an integer number (44864362041).

Almost surely, 2^89728724081 is an apocalyptic number.

It is an amenable number.

89728724081 is a deficient number, since it is larger than the sum of its proper divisors (1).

89728724081 is an equidigital number, since it uses as much as digits as its factorization.

89728724081 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 3612672, while the sum is 56.

The spelling of 89728724081 in words is "eighty-nine billion, seven hundred twenty-eight million, seven hundred twenty-four thousand, eighty-one".