21248835 has 16 divisors (see below), whose sum is σ = 34102944. Its totient is φ = 11297792.

The previous prime is 21248831. The next prime is 21248879. The reversal of 21248835 is 53884212.

It is a cyclic number.

It is not a de Polignac number, because 21248835 - 2² = 21248831 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 21248796 and 21248805.

It is not an unprimeable number, because it can be changed into a prime (21248831) 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 15 ways as a sum of consecutive naturals, for example, 3289 + ... + 7301.

It is an arithmetic number, because the mean of its divisors is an integer number (2131434).

Almost surely, 2^21248835 is an apocalyptic number.

21248835 is a deficient number, since it is larger than the sum of its proper divisors (12854109).

21248835 is a wasteful number, since it uses less digits than its factorization.

21248835 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4374.

The product of its digits is 15360, while the sum is 33.

The square root of 21248835 is about 4609.6458649228. The cubic root of 21248835 is about 276.9778510183.

The spelling of 21248835 in words is "twenty-one million, two hundred forty-eight thousand, eight hundred thirty-five".