21900219 has 16 divisors (see below), whose sum is σ = 32294784. Its totient is φ = 13089600.

The previous prime is 21900181. The next prime is 21900227. The reversal of 21900219 is 91200912.

It is not a de Polignac number, because 21900219 - 2⁷ = 21900091 is a prime.

It is a super-2 number, since 2×21900219² = 959239184495922, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (21900259) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 2137 + ... + 6954.

It is an arithmetic number, because the mean of its divisors is an integer number (2018424).

Almost surely, 2^21900219 is an apocalyptic number.

21900219 is a deficient number, since it is larger than the sum of its proper divisors (10394565).

21900219 is a wasteful number, since it uses less digits than its factorization.

21900219 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9178.

The product of its (nonzero) digits is 324, while the sum is 24.

The square root of 21900219 is about 4679.7669813785. The cubic root of 21900219 is about 279.7796693554.

It can be divided in two parts, 21900 and 219, that multiplied together give a square (4796100 = 2190²).

The spelling of 21900219 in words is "twenty-one million, nine hundred thousand, two hundred nineteen".