20210956663 has 2 divisors, whose sum is σ = 20210956664. Its totient is φ = 20210956662.

The previous prime is 20210956613. The next prime is 20210956679. The reversal of 20210956663 is 36665901202.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 20210956663 - 2⁹ = 20210956151 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (20210956603) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10105478331 + 10105478332.

It is an arithmetic number, because the mean of its divisors is an integer number (10105478332).

Almost surely, 2^20210956663 is an apocalyptic number.

20210956663 is a deficient number, since it is larger than the sum of its proper divisors (1).

20210956663 is an equidigital number, since it uses as much as digits as its factorization.

20210956663 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 116640, while the sum is 40.

The spelling of 20210956663 in words is "twenty billion, two hundred ten million, nine hundred fifty-six thousand, six hundred sixty-three".