21619089 has 8 divisors (see below), whose sum is σ = 32028320. Its totient is φ = 14412708.

The previous prime is 21619051. The next prime is 21619109. The reversal of 21619089 is 98091612.

It is not a de Polignac number, because 21619089 - 2¹⁵ = 21586321 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (21619009) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 400327 + ... + 400380.

It is an arithmetic number, because the mean of its divisors is an integer number (4003540).

Almost surely, 2^21619089 is an apocalyptic number.

It is an amenable number.

21619089 is a deficient number, since it is larger than the sum of its proper divisors (10409231).

21619089 is an equidigital number, since it uses as much as digits as its factorization.

21619089 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 800716 (or 800710 counting only the distinct ones).

The product of its (nonzero) digits is 7776, while the sum is 36.

The square root of 21619089 is about 4649.6332113404. The cubic root of 21619089 is about 278.5773459436.

The spelling of 21619089 in words is "twenty-one million, six hundred nineteen thousand, eighty-nine".