84090921 has 8 divisors (see below), whose sum is σ = 116996160. Its totient is φ = 53623152.

The previous prime is 84090911. The next prime is 84090931. The reversal of 84090921 is 12909048.

It is an interprime number because it is at equal distance from previous prime (84090911) and next prime (84090931).

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

It is not a de Polignac number, because 84090921 - 2⁷ = 84090793 is a prime.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (84090911) 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, 609286 + ... + 609423.

It is an arithmetic number, because the mean of its divisors is an integer number (14624520).

Almost surely, 2^84090921 is an apocalyptic number.

It is an amenable number.

84090921 is a deficient number, since it is larger than the sum of its proper divisors (32905239).

84090921 is a wasteful number, since it uses less digits than its factorization.

84090921 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1218735.

The product of its (nonzero) digits is 5184, while the sum is 33.

The square root of 84090921 is about 9170.1101956301. The cubic root of 84090921 is about 438.1098690205.

Adding to 84090921 its reverse (12909048), we get a palindrome (96999969).

The spelling of 84090921 in words is "eighty-four million, ninety thousand, nine hundred twenty-one".