89724989 has 2 divisors, whose sum is σ = 89724990. Its totient is φ = 89724988.

The previous prime is 89724983. The next prime is 89724991. The reversal of 89724989 is 98942798.

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., 79959364 + 9765625 = 8942^2 + 3125^2 .

It is a cyclic number.

It is not a de Polignac number, because 89724989 - 2²⁴ = 72947773 is a prime.

It is a super-4 number, since 4×89724989⁴ (a number of 33 digits) contains 4444 as substring.

Together with 89724991, it forms a pair of twin primes.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (89724983) by changing a digit.

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, 44862494 + 44862495.

It is an arithmetic number, because the mean of its divisors is an integer number (44862495).

Almost surely, 2^89724989 is an apocalyptic number.

It is an amenable number.

89724989 is a deficient number, since it is larger than the sum of its proper divisors (1).

89724989 is an equidigital number, since it uses as much as digits as its factorization.

89724989 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 2612736, while the sum is 56.

The square root of 89724989 is about 9472.3275386781. The cubic root of 89724989 is about 447.6835513058.

The spelling of 89724989 in words is "eighty-nine million, seven hundred twenty-four thousand, nine hundred eighty-nine".