20471145397 has 2 divisors, whose sum is σ = 20471145398. Its totient is φ = 20471145396.

The previous prime is 20471145329. The next prime is 20471145451. The reversal of 20471145397 is 79354117402.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 19307380401 + 1163764996 = 138951^2 + 34114^2 .

It is a cyclic number.

It is not a de Polignac number, because 20471145397 - 2³¹ = 18323661749 is a prime.

It is a super-2 number, since 2×20471145397² (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 (20471145197) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10235572698 + 10235572699.

It is an arithmetic number, because the mean of its divisors is an integer number (10235572699).

Almost surely, 2^20471145397 is an apocalyptic number.

It is an amenable number.

20471145397 is a deficient number, since it is larger than the sum of its proper divisors (1).

20471145397 is an equidigital number, since it uses as much as digits as its factorization.

20471145397 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 211680, while the sum is 43.

The spelling of 20471145397 in words is "twenty billion, four hundred seventy-one million, one hundred forty-five thousand, three hundred ninety-seven".