21889519 has 4 divisors (see below), whose sum is σ = 22644360. Its totient is φ = 21134680.

The previous prime is 21889499. The next prime is 21889529. The reversal of 21889519 is 91598812.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 21889519 - 2⁵ = 21889487 is a prime.

It is a super-2 number, since 2×21889519² = 958302084102722, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21889529) 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, 377377 + ... + 377434.

It is an arithmetic number, because the mean of its divisors is an integer number (5661090).

Almost surely, 2^21889519 is an apocalyptic number.

21889519 is a gapful number since it is divisible by the number (29) formed by its first and last digit.

21889519 is a deficient number, since it is larger than the sum of its proper divisors (754841).

21889519 is an equidigital number, since it uses as much as digits as its factorization.

21889519 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 754840.

The product of its digits is 51840, while the sum is 43.

The square root of 21889519 is about 4678.6236223915. The cubic root of 21889519 is about 279.7340970541.

The spelling of 21889519 in words is "twenty-one million, eight hundred eighty-nine thousand, five hundred nineteen".