21719049 has 8 divisors (see below), whose sum is σ = 31591392. Its totient is φ = 13163040.

The previous prime is 21719041. The next prime is 21719051. The reversal of 21719049 is 94091712.

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

It is not a de Polignac number, because 21719049 - 2³ = 21719041 is a prime.

It is a Smith number, since the sum of its digits (33) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a Harshad number since it is a multiple of its sum of digits (33), and also a Moran number because the ratio is a prime number: 658153 = 21719049 / (2 + 1 + 7 + 1 + 9 + 0 + 4 + 9).

It is not an unprimeable number, because it can be changed into a prime (21719041) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 329044 + ... + 329109.

It is an arithmetic number, because the mean of its divisors is an integer number (3948924).

Almost surely, 2^21719049 is an apocalyptic number.

It is an amenable number.

21719049 is a deficient number, since it is larger than the sum of its proper divisors (9872343).

21719049 is a wasteful number, since it uses less digits than its factorization.

21719049 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 658167.

The product of its (nonzero) digits is 4536, while the sum is 33.

The square root of 21719049 is about 4660.3700496849. The cubic root of 21719049 is about 279.0060378185.

The spelling of 21719049 in words is "twenty-one million, seven hundred nineteen thousand, forty-nine".