1021200120001 has 2 divisors, whose sum is σ = 1021200120002. Its totient is φ = 1021200120000.

The previous prime is 1021200119987. The next prime is 1021200120019. The reversal of 1021200120001 is 1000210021201.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 697143172401 + 324056947600 = 834951^2 + 569260^2 .

It is a cyclic number.

It is not a de Polignac number, because 1021200120001 - 2²³ = 1021191731393 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 1021200120001.

It is not a weakly prime, because it can be changed into another prime (1021200120071) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 510600060000 + 510600060001.

It is an arithmetic number, because the mean of its divisors is an integer number (510600060001).

Almost surely, 2^{1021200120001} is an apocalyptic number.

It is an amenable number.

1021200120001 is a deficient number, since it is larger than the sum of its proper divisors (1).

1021200120001 is an equidigital number, since it uses as much as digits as its factorization.

1021200120001 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 8, while the sum is 10.

Adding to 1021200120001 its reverse (1000210021201), we get a palindrome (2021410141202).

The spelling of 1021200120001 in words is "one trillion, twenty-one billion, two hundred million, one hundred twenty thousand, one".