21148646 has 8 divisors (see below), whose sum is σ = 33589080. Its totient is φ = 9952288.

The previous prime is 21148601. The next prime is 21148667. The reversal of 21148646 is 64684112.

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

It is a Curzon number.

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 in 3 ways as a sum of consecutive naturals, for example, 310976 + ... + 311043.

It is an arithmetic number, because the mean of its divisors is an integer number (4198635).

Almost surely, 2^21148646 is an apocalyptic number.

21148646 is a deficient number, since it is larger than the sum of its proper divisors (12440434).

21148646 is a wasteful number, since it uses less digits than its factorization.

21148646 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 622038.

The product of its digits is 9216, while the sum is 32.

The square root of 21148646 is about 4598.7657039688. The cubic root of 21148646 is about 276.5418449532.

The spelling of 21148646 in words is "twenty-one million, one hundred forty-eight thousand, six hundred forty-six".