89965781 has 2 divisors, whose sum is σ = 89965782. Its totient is φ = 89965780.

The previous prime is 89965747. The next prime is 89965783. The reversal of 89965781 is 18756998.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 79299025 + 10666756 = 8905^2 + 3266^2 .

It is a cyclic number.

It is not a de Polignac number, because 89965781 - 2¹⁸ = 89703637 is a prime.

It is a super-2 number, since 2×89965781² = 16187683501879922, which contains 22 as substring.

Together with 89965783, 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 (89965783) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 44982890 + 44982891.

It is an arithmetic number, because the mean of its divisors is an integer number (44982891).

Almost surely, 2^89965781 is an apocalyptic number.

It is an amenable number.

89965781 is a deficient number, since it is larger than the sum of its proper divisors (1).

89965781 is an equidigital number, since it uses as much as digits as its factorization.

89965781 is an evil number, because the sum of its binary digits is even.

The product of its digits is 1088640, while the sum is 53.

The square root of 89965781 is about 9485.0293093907. The cubic root of 89965781 is about 448.0836714601.

The spelling of 89965781 in words is "eighty-nine million, nine hundred sixty-five thousand, seven hundred eighty-one".