90987879 has 8 divisors (see below), whose sum is σ = 121551232. Its totient is φ = 60541560.

The previous prime is 90987851. The next prime is 90987881. The reversal of 90987879 is 97878909.

It is a happy number.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 90987879 - 2¹³ = 90979687 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (90987829) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 27427 + ... + 30564.

It is an arithmetic number, because the mean of its divisors is an integer number (15193904).

Almost surely, 2^90987879 is an apocalyptic number.

90987879 is a deficient number, since it is larger than the sum of its proper divisors (30563353).

90987879 is a wasteful number, since it uses less digits than its factorization.

90987879 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 58517.

The product of its (nonzero) digits is 2286144, while the sum is 57.

The square root of 90987879 is about 9538.7566799872. The cubic root of 90987879 is about 449.7741731103.

It can be divided in two parts, 909 and 87879, that added together give a palindrome (88788).

The spelling of 90987879 in words is "ninety million, nine hundred eighty-seven thousand, eight hundred seventy-nine".