20623381081 has 2 divisors, whose sum is σ = 20623381082. Its totient is φ = 20623381080.

The previous prime is 20623381063. The next prime is 20623381127. The reversal of 20623381081 is 18018332602.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 17222625225 + 3400755856 = 131235^2 + 58316^2 .

It is a cyclic number.

It is not a de Polignac number, because 20623381081 - 2¹⁵ = 20623348313 is a prime.

It is a super-2 number, since 2×20623381081² (a number of 21 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (20623351081) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10311690540 + 10311690541.

It is an arithmetic number, because the mean of its divisors is an integer number (10311690541).

Almost surely, 2^20623381081 is an apocalyptic number.

It is an amenable number.

20623381081 is a deficient number, since it is larger than the sum of its proper divisors (1).

20623381081 is an equidigital number, since it uses as much as digits as its factorization.

20623381081 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 13824, while the sum is 34.

The spelling of 20623381081 in words is "twenty billion, six hundred twenty-three million, three hundred eighty-one thousand, eighty-one".