20284181977 has 2 divisors, whose sum is σ = 20284181978. Its totient is φ = 20284181976.

The previous prime is 20284181971. The next prime is 20284182031. The reversal of 20284181977 is 77918148202.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 17560490256 + 2723691721 = 132516^2 + 52189^2 .

It is a cyclic number.

It is not a de Polignac number, because 20284181977 - 2³ = 20284181969 is a prime.

It is a super-2 number, since 2×20284181977² (a number of 21 digits) contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 20284181977.

It is not a weakly prime, because it can be changed into another prime (20284181971) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10142090988 + 10142090989.

It is an arithmetic number, because the mean of its divisors is an integer number (10142090989).

Almost surely, 2^20284181977 is an apocalyptic number.

It is an amenable number.

20284181977 is a deficient number, since it is larger than the sum of its proper divisors (1).

20284181977 is an equidigital number, since it uses as much as digits as its factorization.

20284181977 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 451584, while the sum is 49.

The spelling of 20284181977 in words is "twenty billion, two hundred eighty-four million, one hundred eighty-one thousand, nine hundred seventy-seven".