21149574 has 8 divisors (see below), whose sum is σ = 42299160. Its totient is φ = 7049856.

The previous prime is 21149561. The next prime is 21149599. The reversal of 21149574 is 47594112.

It is a happy number.

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

21149574 is an admirable number.

It is a congruent number.

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, 1762459 + ... + 1762470.

It is an arithmetic number, because the mean of its divisors is an integer number (5287395).

Almost surely, 2^21149574 is an apocalyptic number.

21149574 is a primitive abundant number, since it is smaller than the sum of its proper divisors, none of which is abundant.

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

21149574 is a wasteful number, since it uses less digits than its factorization.

21149574 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3524934.

The product of its digits is 10080, while the sum is 33.

The square root of 21149574 is about 4598.8665995004. The cubic root of 21149574 is about 276.5458897682.

The spelling of 21149574 in words is "twenty-one million, one hundred forty-nine thousand, five hundred seventy-four".