90878289 has 4 divisors (see below), whose sum is σ = 121171056. Its totient is φ = 60585524.

The previous prime is 90878269. The next prime is 90878297. The reversal of 90878289 is 98287809.

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 90878289 - 2⁹ = 90877777 is a prime.

It is not an unprimeable number, because it can be changed into a prime (90878269) 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 in 3 ways as a sum of consecutive naturals, for example, 15146379 + ... + 15146384.

It is an arithmetic number, because the mean of its divisors is an integer number (30292764).

Almost surely, 2^90878289 is an apocalyptic number.

It is an amenable number.

90878289 is a deficient number, since it is larger than the sum of its proper divisors (30292767).

90878289 is a wasteful number, since it uses less digits than its factorization.

90878289 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 30292766.

The product of its (nonzero) digits is 580608, while the sum is 51.

The square root of 90878289 is about 9533.0104898715. The cubic root of 90878289 is about 449.5935243075.

It can be divided in two parts, 908 and 78289, that added together give a palindrome (79197).

The spelling of 90878289 in words is "ninety million, eight hundred seventy-eight thousand, two hundred eighty-nine".