21148679 has 2 divisors, whose sum is σ = 21148680. Its totient is φ = 21148678.

The previous prime is 21148667. The next prime is 21148703. The reversal of 21148679 is 97684112.

It is a weak prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21148679 is a prime.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21148079) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10574339 + 10574340.

It is an arithmetic number, because the mean of its divisors is an integer number (10574340).

Almost surely, 2^21148679 is an apocalyptic number.

21148679 is a deficient number, since it is larger than the sum of its proper divisors (1).

21148679 is an equidigital number, since it uses as much as digits as its factorization.

21148679 is an evil number, because the sum of its binary digits is even.

The product of its digits is 24192, while the sum is 38.

The square root of 21148679 is about 4598.7692918867. The cubic root of 21148679 is about 276.5419887903.

The spelling of 21148679 in words is "twenty-one million, one hundred forty-eight thousand, six hundred seventy-nine".