21627679 has 2 divisors, whose sum is σ = 21627680. Its totient is φ = 21627678.

The previous prime is 21627629. The next prime is 21627713. The reversal of 21627679 is 97672612.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 21627679 - 2⁹ = 21627167 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21627629) 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 as a sum of consecutive naturals, namely, 10813839 + 10813840.

It is an arithmetic number, because the mean of its divisors is an integer number (10813840).

Almost surely, 2^21627679 is an apocalyptic number.

21627679 is a deficient number, since it is larger than the sum of its proper divisors (1).

21627679 is an equidigital number, since it uses as much as digits as its factorization.

21627679 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 63504, while the sum is 40.

The square root of 21627679 is about 4650.5568483785. The cubic root of 21627679 is about 278.6142371456.

The spelling of 21627679 in words is "twenty-one million, six hundred twenty-seven thousand, six hundred seventy-nine".