2001021481 has 2 divisors, whose sum is σ = 2001021482. Its totient is φ = 2001021480.

The previous prime is 2001021433. The next prime is 2001021487. The reversal of 2001021481 is 1841201002.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 1306171881 + 694849600 = 36141^2 + 26360^2 .

It is a cyclic number.

It is not a de Polignac number, because 2001021481 - 2¹⁹ = 2000497193 is a prime.

It is a super-2 number, since 2×2001021481² = 8008173934846866722, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (2001021487) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1000510740 + 1000510741.

It is an arithmetic number, because the mean of its divisors is an integer number (1000510741).

Almost surely, 2^2001021481 is an apocalyptic number.

It is an amenable number.

2001021481 is a deficient number, since it is larger than the sum of its proper divisors (1).

2001021481 is an equidigital number, since it uses as much as digits as its factorization.

2001021481 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 128, while the sum is 19.

The square root of 2001021481 is about 44732.7785969081. The cubic root of 2001021481 is about 1260.1355109567.

Adding to 2001021481 its reverse (1841201002), we get a palindrome (3842222483).

The spelling of 2001021481 in words is "two billion, one million, twenty-one thousand, four hundred eighty-one".