20663655407 has 2 divisors, whose sum is σ = 20663655408. Its totient is φ = 20663655406.

The previous prime is 20663655403. The next prime is 20663655433. The reversal of 20663655407 is 70455636602.

It is a happy number.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 20663655407 - 2² = 20663655403 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (20663655403) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10331827703 + 10331827704.

It is an arithmetic number, because the mean of its divisors is an integer number (10331827704).

Almost surely, 2^20663655407 is an apocalyptic number.

20663655407 is a deficient number, since it is larger than the sum of its proper divisors (1).

20663655407 is an equidigital number, since it uses as much as digits as its factorization.

20663655407 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 907200, while the sum is 44.

The spelling of 20663655407 in words is "twenty billion, six hundred sixty-three million, six hundred fifty-five thousand, four hundred seven".