10021211861 has 2 divisors, whose sum is σ = 10021211862. Its totient is φ = 10021211860.

The previous prime is 10021211839. The next prime is 10021211881. The reversal of 10021211861 is 16811212001.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 10021211236 + 625 = 100106^2 + 25^2 .

It is a cyclic number.

It is not a de Polignac number, because 10021211861 - 2¹⁸ = 10020949717 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (10021211881) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 5010605930 + 5010605931.

It is an arithmetic number, because the mean of its divisors is an integer number (5010605931).

Almost surely, 2^10021211861 is an apocalyptic number.

It is an amenable number.

10021211861 is a deficient number, since it is larger than the sum of its proper divisors (1).

10021211861 is an equidigital number, since it uses as much as digits as its factorization.

10021211861 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 192, while the sum is 23.

Adding to 10021211861 its reverse (16811212001), we get a palindrome (26832423862).

The spelling of 10021211861 in words is "ten billion, twenty-one million, two hundred eleven thousand, eight hundred sixty-one".