20806462961 has 2 divisors, whose sum is σ = 20806462962. Its totient is φ = 20806462960.

The previous prime is 20806462949. The next prime is 20806463011. The reversal of 20806462961 is 16926460802.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 20550942736 + 255520225 = 143356^2 + 15985^2 .

It is a cyclic number.

It is not a de Polignac number, because 20806462961 - 2¹⁸ = 20806200817 is a prime.

It is not a weakly prime, because it can be changed into another prime (20806462861) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10403231480 + 10403231481.

It is an arithmetic number, because the mean of its divisors is an integer number (10403231481).

Almost surely, 2^20806462961 is an apocalyptic number.

It is an amenable number.

20806462961 is a deficient number, since it is larger than the sum of its proper divisors (1).

20806462961 is an equidigital number, since it uses as much as digits as its factorization.

20806462961 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 248832, while the sum is 44.

The spelling of 20806462961 in words is "twenty billion, eight hundred six million, four hundred sixty-two thousand, nine hundred sixty-one".