1001210981 has 2 divisors, whose sum is σ = 1001210982. Its totient is φ = 1001210980.

The previous prime is 1001210911. The next prime is 1001211017. The reversal of 1001210981 is 1890121001.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 576480100 + 424730881 = 24010^2 + 20609^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1001210981 is a prime.

It is a super-2 number, since 2×1001210981² = 2004846856949964722, which contains 22 as substring.

It is a Sophie Germain prime.

It is a Curzon number.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1001210911) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 500605490 + 500605491.

It is an arithmetic number, because the mean of its divisors is an integer number (500605491).

Almost surely, 2^1001210981 is an apocalyptic number.

It is an amenable number.

1001210981 is a deficient number, since it is larger than the sum of its proper divisors (1).

1001210981 is an equidigital number, since it uses as much as digits as its factorization.

1001210981 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 144, while the sum is 23.

The square root of 1001210981 is about 31641.9180992556. The cubic root of 1001210981 is about 1000.4034975012.

Adding to 1001210981 its reverse (1890121001), we get a palindrome (2891331982).

The spelling of 1001210981 in words is "one billion, one million, two hundred ten thousand, nine hundred eighty-one".