21676279 has 2 divisors, whose sum is σ = 21676280. Its totient is φ = 21676278.

The previous prime is 21676273. The next prime is 21676297. The reversal of 21676279 is 97267612.

Together with next prime (21676297) it forms an Ormiston pair, because they use the same digits, order apart.

It is a weak prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21676279 is a prime.

It is a super-2 number, since 2×21676279² = 939722142571682, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21676273) by changing a digit.

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 as a sum of consecutive naturals, namely, 10838139 + 10838140.

It is an arithmetic number, because the mean of its divisors is an integer number (10838140).

Almost surely, 2^21676279 is an apocalyptic number.

21676279 is a deficient number, since it is larger than the sum of its proper divisors (1).

21676279 is an equidigital number, since it uses as much as digits as its factorization.

21676279 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 21676279 is about 4655.7790969933. The cubic root of 21676279 is about 278.8227742718.

The spelling of 21676279 in words is "twenty-one million, six hundred seventy-six thousand, two hundred seventy-nine".