20000002181 has 2 divisors, whose sum is σ = 20000002182. Its totient is φ = 20000002180.

The previous prime is 20000002159. The next prime is 20000002213. The reversal of 20000002181 is 18120000002.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 19996505281 + 3496900 = 141409^2 + 1870^2 .

It is a cyclic number.

It is not a de Polignac number, because 20000002181 - 2¹⁸ = 19999740037 is a prime.

It is a super-2 number, since 2×20000002181² (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 (20000002111) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10000001090 + 10000001091.

It is an arithmetic number, because the mean of its divisors is an integer number (10000001091).

Almost surely, 2^20000002181 is an apocalyptic number.

It is an amenable number.

20000002181 is a deficient number, since it is larger than the sum of its proper divisors (1).

20000002181 is an equidigital number, since it uses as much as digits as its factorization.

20000002181 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 32, while the sum is 14.

Adding to 20000002181 its reverse (18120000002), we get a palindrome (38120002183).

The spelling of 20000002181 in words is "twenty billion, two thousand, one hundred eighty-one".