21121002212801 has 2 divisors, whose sum is σ = 21121002212802. Its totient is φ = 21121002212800.

The previous prime is 21121002212749. The next prime is 21121002212887. The reversal of 21121002212801 is 10821220012112.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 20898392818576 + 222609394225 = 4571476^2 + 471815^2 .

It is a cyclic number.

It is not a de Polignac number, because 21121002212801 - 2³⁸ = 20846124305857 is a prime.

It is not a weakly prime, because it can be changed into another prime (21121002214801) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10560501106400 + 10560501106401.

It is an arithmetic number, because the mean of its divisors is an integer number (10560501106401).

Almost surely, 2^{21121002212801} is an apocalyptic number.

It is an amenable number.

21121002212801 is a deficient number, since it is larger than the sum of its proper divisors (1).

21121002212801 is an equidigital number, since it uses as much as digits as its factorization.

21121002212801 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 256, while the sum is 23.

Adding to 21121002212801 its reverse (10821220012112), we get a palindrome (31942222224913).

The spelling of 21121002212801 in words is "twenty-one trillion, one hundred twenty-one billion, two million, two hundred twelve thousand, eight hundred one".