20906629 has 2 divisors, whose sum is σ = 20906630. Its totient is φ = 20906628.

The previous prime is 20906581. The next prime is 20906647. The reversal of 20906629 is 92660902.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 11573604 + 9333025 = 3402^2 + 3055^2 .

It is a cyclic number.

It is not a de Polignac number, because 20906629 - 2¹⁵ = 20873861 is a prime.

It is a super-2 number, since 2×20906629² = 874174272287282, which contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 20906594 and 20906603.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (20906329) 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, 10453314 + 10453315.

It is an arithmetic number, because the mean of its divisors is an integer number (10453315).

Almost surely, 2^20906629 is an apocalyptic number.

It is an amenable number.

20906629 is a deficient number, since it is larger than the sum of its proper divisors (1).

20906629 is an equidigital number, since it uses as much as digits as its factorization.

20906629 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 11664, while the sum is 34.

The square root of 20906629 is about 4572.3767342598. The cubic root of 20906629 is about 275.4829156635.

The spelling of 20906629 in words is "twenty million, nine hundred six thousand, six hundred twenty-nine".