20540044381 has 2 divisors, whose sum is σ = 20540044382. Its totient is φ = 20540044380.

The previous prime is 20540044367. The next prime is 20540044417. The reversal of 20540044381 is 18344004502.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 18472887225 + 2067157156 = 135915^2 + 45466^2 .

It is a cyclic number.

It is not a de Polignac number, because 20540044381 - 2⁹ = 20540043869 is a prime.

It is a super-2 number, since 2×20540044381² (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 (20540144381) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10270022190 + 10270022191.

It is an arithmetic number, because the mean of its divisors is an integer number (10270022191).

Almost surely, 2^20540044381 is an apocalyptic number.

It is an amenable number.

20540044381 is a deficient number, since it is larger than the sum of its proper divisors (1).

20540044381 is an equidigital number, since it uses as much as digits as its factorization.

20540044381 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 15360, while the sum is 31.

Adding to 20540044381 its reverse (18344004502), we get a palindrome (38884048883).

The spelling of 20540044381 in words is "twenty billion, five hundred forty million, forty-four thousand, three hundred eighty-one".