21719842 has 8 divisors (see below), whose sum is σ = 32716800. Its totient is φ = 10814244.

The previous prime is 21719833. The next prime is 21719857. The reversal of 21719842 is 24891712.

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

It is a junction number, because it is equal to n+sod(n) for n = 21719798 and 21719807.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 22242 + ... + 23197.

It is an arithmetic number, because the mean of its divisors is an integer number (4089600).

Almost surely, 2^21719842 is an apocalyptic number.

21719842 is a deficient number, since it is larger than the sum of its proper divisors (10996958).

21719842 is a wasteful number, since it uses less digits than its factorization.

21719842 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 45680.

The product of its digits is 8064, while the sum is 34.

The square root of 21719842 is about 4660.4551279891. The cubic root of 21719842 is about 279.0094334413.

The spelling of 21719842 in words is "twenty-one million, seven hundred nineteen thousand, eight hundred forty-two".