21649006 has 4 divisors (see below), whose sum is σ = 32473512. Its totient is φ = 10824502.

The previous prime is 21648997. The next prime is 21649031. The reversal of 21649006 is 60094612.

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

It is a super-3 number, since 3×21649006³ (a number of 23 digits) contains 333 as substring.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 5412250 + ... + 5412253.

It is an arithmetic number, because the mean of its divisors is an integer number (8118378).

Almost surely, 2^21649006 is an apocalyptic number.

21649006 is a deficient number, since it is larger than the sum of its proper divisors (10824506).

21649006 is a wasteful number, since it uses less digits than its factorization.

21649006 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10824505.

The product of its (nonzero) digits is 2592, while the sum is 28.

The square root of 21649006 is about 4652.8492346088. The cubic root of 21649006 is about 278.7057873264.

The spelling of 21649006 in words is "twenty-one million, six hundred forty-nine thousand, six".