21007148 has 6 divisors (see below), whose sum is σ = 36762516. Its totient is φ = 10503572.

The previous prime is 21007139. The next prime is 21007153. The reversal of 21007148 is 84170012.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 2625890 + ... + 2625897.

It is an arithmetic number, because the mean of its divisors is an integer number (6127086).

Almost surely, 2^21007148 is an apocalyptic number.

It is an amenable number.

21007148 is a deficient number, since it is larger than the sum of its proper divisors (15755368).

21007148 is a wasteful number, since it uses less digits than its factorization.

21007148 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5251791 (or 5251789 counting only the distinct ones).

The product of its (nonzero) digits is 448, while the sum is 23.

The square root of 21007148 is about 4583.3555393401. The cubic root of 21007148 is about 275.9237169284.

The spelling of 21007148 in words is "twenty-one million, seven thousand, one hundred forty-eight".