20605863511 has 2 divisors, whose sum is σ = 20605863512. Its totient is φ = 20605863510.

The previous prime is 20605863491. The next prime is 20605863529. The reversal of 20605863511 is 11536850602.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 20605863511 - 2⁵ = 20605863479 is a prime.

It is a super-2 number, since 2×20605863511² (a number of 21 digits) contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (20605863541) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10302931755 + 10302931756.

It is an arithmetic number, because the mean of its divisors is an integer number (10302931756).

Almost surely, 2^20605863511 is an apocalyptic number.

20605863511 is a deficient number, since it is larger than the sum of its proper divisors (1).

20605863511 is an equidigital number, since it uses as much as digits as its factorization.

20605863511 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 43200, while the sum is 37.

The spelling of 20605863511 in words is "twenty billion, six hundred five million, eight hundred sixty-three thousand, five hundred eleven".