89987989 has 32 divisors (see below), whose sum is σ = 115153920. Its totient is φ = 68428800.

The previous prime is 89987929. The next prime is 89988001. The reversal of 89987989 is 98978998.

89987989 = T₁₉₅ + T₁₉₆ + ... + T₈₁₇.

It is a happy number.

It is a cyclic number.

It is not a de Polignac number, because 89987989 - 2⁷ = 89987861 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (89987929) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 331924 + ... + 332194.

It is an arithmetic number, because the mean of its divisors is an integer number (3598560).

Almost surely, 2^89987989 is an apocalyptic number.

89987989 is a gapful number since it is divisible by the number (89) formed by its first and last digit.

It is an amenable number.

89987989 is a deficient number, since it is larger than the sum of its proper divisors (25165931).

89987989 is a wasteful number, since it uses less digits than its factorization.

89987989 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 421.

The product of its digits is 23514624, while the sum is 67.

The square root of 89987989 is about 9486.1999241003. The cubic root of 89987989 is about 448.1205381568.

It can be divided in two parts, 899 and 87989, that added together give a palindrome (88888).

The spelling of 89987989 in words is "eighty-nine million, nine hundred eighty-seven thousand, nine hundred eighty-nine".