20667397 has 2 divisors, whose sum is σ = 20667398. Its totient is φ = 20667396.

The previous prime is 20667389. The next prime is 20667433. The reversal of 20667397 is 79376602.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 13771521 + 6895876 = 3711^2 + 2626^2 .

It is a cyclic number.

It is not a de Polignac number, because 20667397 - 2³ = 20667389 is a prime.

It is a super-3 number, since 3×20667397³ (a number of 23 digits) contains 333 as substring.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (20667377) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10333698 + 10333699.

It is an arithmetic number, because the mean of its divisors is an integer number (10333699).

Almost surely, 2^20667397 is an apocalyptic number.

It is an amenable number.

20667397 is a deficient number, since it is larger than the sum of its proper divisors (1).

20667397 is an equidigital number, since it uses as much as digits as its factorization.

20667397 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 95256, while the sum is 40.

The square root of 20667397 is about 4546.1408909096. The cubic root of 20667397 is about 274.4281095919.

The spelling of 20667397 in words is "twenty million, six hundred sixty-seven thousand, three hundred ninety-seven".