21000419 has 4 divisors (see below), whose sum is σ = 22909560. Its totient is φ = 19091280.

The previous prime is 21000407. The next prime is 21000433. The reversal of 21000419 is 91400012.

It is a happy number.

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 21000419 - 2¹⁶ = 20934883 is a prime.

It is a super-2 number, since 2×21000419² = 882035196351122, which contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 21000397 and 21000406.

It is not an unprimeable number, because it can be changed into a prime (21008419) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 954554 + ... + 954575.

It is an arithmetic number, because the mean of its divisors is an integer number (5727390).

Almost surely, 2^21000419 is an apocalyptic number.

21000419 is a deficient number, since it is larger than the sum of its proper divisors (1909141).

21000419 is a wasteful number, since it uses less digits than its factorization.

21000419 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1909140.

The product of its (nonzero) digits is 72, while the sum is 17.

The square root of 21000419 is about 4582.6214113758. The cubic root of 21000419 is about 275.8942525294.

The spelling of 21000419 in words is "twenty-one million, four hundred nineteen", and thus it is an aban number.