20668667 has 2 divisors, whose sum is σ = 20668668. Its totient is φ = 20668666.

The previous prime is 20668657. The next prime is 20668693. The reversal of 20668667 is 76686602.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 20668667 - 2¹⁸ = 20406523 is a prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (20668657) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10334333 + 10334334.

It is an arithmetic number, because the mean of its divisors is an integer number (10334334).

Almost surely, 2^20668667 is an apocalyptic number.

20668667 is a deficient number, since it is larger than the sum of its proper divisors (1).

20668667 is an equidigital number, since it uses as much as digits as its factorization.

20668667 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 145152, while the sum is 41.

The square root of 20668667 is about 4546.2805676729. The cubic root of 20668667 is about 274.4337306281.

The spelling of 20668667 in words is "twenty million, six hundred sixty-eight thousand, six hundred sixty-seven".