81036289 has 4 divisors (see below), whose sum is σ = 81248256. Its totient is φ = 80824324.

The previous prime is 81036283. The next prime is 81036359. The reversal of 81036289 is 98263018.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 81036289 - 2³ = 81036281 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (81036281) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 105409 + ... + 106174.

It is an arithmetic number, because the mean of its divisors is an integer number (20312064).

Almost surely, 2^81036289 is an apocalyptic number.

It is an amenable number.

81036289 is a deficient number, since it is larger than the sum of its proper divisors (211967).

81036289 is a wasteful number, since it uses less digits than its factorization.

81036289 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 211966.

The product of its (nonzero) digits is 20736, while the sum is 37.

The square root of 81036289 is about 9002.0158298017. The cubic root of 81036289 is about 432.7394760066.

The spelling of 81036289 in words is "eighty-one million, thirty-six thousand, two hundred eighty-nine".