21682699 has 2 divisors, whose sum is σ = 21682700. Its totient is φ = 21682698.

The previous prime is 21682697. The next prime is 21682709. The reversal of 21682699 is 99628612.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 21682699 - 2¹ = 21682697 is a prime.

Together with 21682697, it forms a pair of twin primes.

It is not a weakly prime, because it can be changed into another prime (21682693) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10841349 + 10841350.

It is an arithmetic number, because the mean of its divisors is an integer number (10841350).

Almost surely, 2^21682699 is an apocalyptic number.

21682699 is a deficient number, since it is larger than the sum of its proper divisors (1).

21682699 is an equidigital number, since it uses as much as digits as its factorization.

21682699 is an evil number, because the sum of its binary digits is even.

The product of its digits is 93312, while the sum is 43.

The square root of 21682699 is about 4656.4685116513. The cubic root of 21682699 is about 278.8502984534.

The spelling of 21682699 in words is "twenty-one million, six hundred eighty-two thousand, six hundred ninety-nine".