20021081 has 2 divisors, whose sum is σ = 20021082. Its totient is φ = 20021080.

The previous prime is 20021069. The next prime is 20021093. The reversal of 20021081 is 18012002.

It is a balanced prime because it is at equal distance from previous prime (20021069) and next prime (20021093).

It can be written as a sum of positive squares in only one way, i.e., 18619225 + 1401856 = 4315^2 + 1184^2 .

It is a cyclic number.

It is not a de Polignac number, because 20021081 - 2²² = 15826777 is a prime.

It is a super-2 number, since 2×20021081² = 801687368817122, which contains 22 as substring.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (20021021) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10010540 + 10010541.

It is an arithmetic number, because the mean of its divisors is an integer number (10010541).

Almost surely, 2^20021081 is an apocalyptic number.

It is an amenable number.

20021081 is a deficient number, since it is larger than the sum of its proper divisors (1).

20021081 is an equidigital number, since it uses as much as digits as its factorization.

20021081 is an odious number, because the sum of its binary digits is odd.

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

The square root of 20021081 is about 4474.4922616985. The cubic root of 20021081 is about 271.5370992334.

Adding to 20021081 its reverse (18012002), we get a palindrome (38033083).

The spelling of 20021081 in words is "twenty million, twenty-one thousand, eighty-one".