1021021221601 has 2 divisors, whose sum is σ = 1021021221602. Its totient is φ = 1021021221600.

The previous prime is 1021021221523. The next prime is 1021021221629. The reversal of 1021021221601 is 1061221201201.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 569457381376 + 451563840225 = 754624^2 + 671985^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1021021221601 is a prime.

It is not a weakly prime, because it can be changed into another prime (1021021221641) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 510510610800 + 510510610801.

It is an arithmetic number, because the mean of its divisors is an integer number (510510610801).

Almost surely, 2^{1021021221601} is an apocalyptic number.

It is an amenable number.

1021021221601 is a deficient number, since it is larger than the sum of its proper divisors (1).

1021021221601 is an equidigital number, since it uses as much as digits as its factorization.

1021021221601 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 96, while the sum is 19.

Adding to 1021021221601 its reverse (1061221201201), we get a palindrome (2082242422802).

The spelling of 1021021221601 in words is "one trillion, twenty-one billion, twenty-one million, two hundred twenty-one thousand, six hundred one".