21719006 has 4 divisors (see below), whose sum is σ = 32578512. Its totient is φ = 10859502.

The previous prime is 21718997. The next prime is 21719023. The reversal of 21719006 is 60091712.

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

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 5429750 + ... + 5429753.

It is an arithmetic number, because the mean of its divisors is an integer number (8144628).

Almost surely, 2^21719006 is an apocalyptic number.

21719006 is a deficient number, since it is larger than the sum of its proper divisors (10859506).

21719006 is a wasteful number, since it uses less digits than its factorization.

21719006 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10859505.

The product of its (nonzero) digits is 756, while the sum is 26.

The square root of 21719006 is about 4660.3654363151. The cubic root of 21719006 is about 279.0058536903.

The spelling of 21719006 in words is "twenty-one million, seven hundred nineteen thousand, six".