20717231047 has 2 divisors, whose sum is σ = 20717231048. Its totient is φ = 20717231046.

The previous prime is 20717231027. The next prime is 20717231089. The reversal of 20717231047 is 74013271702.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 20717231047 - 2²³ = 20708842439 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (20717231027) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10358615523 + 10358615524.

It is an arithmetic number, because the mean of its divisors is an integer number (10358615524).

Almost surely, 2^20717231047 is an apocalyptic number.

20717231047 is a deficient number, since it is larger than the sum of its proper divisors (1).

20717231047 is an equidigital number, since it uses as much as digits as its factorization.

20717231047 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 16464, while the sum is 34.

The spelling of 20717231047 in words is "twenty billion, seven hundred seventeen million, two hundred thirty-one thousand, forty-seven".