21619874 has 8 divisors (see below), whose sum is σ = 33220908. Its totient is φ = 10546240.

The previous prime is 21619867. The next prime is 21619879. The reversal of 21619874 is 47891612.

It can be written as a sum of positive squares in 2 ways, for example, as 16362025 + 5257849 = 4045^2 + 2293^2 .

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

It is not an unprimeable number, because it can be changed into a prime (21619879) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 131747 + ... + 131910.

Almost surely, 2^21619874 is an apocalyptic number.

21619874 is a deficient number, since it is larger than the sum of its proper divisors (11601034).

21619874 is a wasteful number, since it uses less digits than its factorization.

21619874 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 263700.

The product of its digits is 24192, while the sum is 38.

The square root of 21619874 is about 4649.7176258349. The cubic root of 21619874 is about 278.5807176640.

The spelling of 21619874 in words is "twenty-one million, six hundred nineteen thousand, eight hundred seventy-four".