221001221020061 has 2 divisors, whose sum is σ = 221001221020062. Its totient is φ = 221001221020060.

The previous prime is 221001221020009. The next prime is 221001221020109. The reversal of 221001221020061 is 160020122100122.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 180260000096836 + 40741220923225 = 13426094^2 + 6382885^2 .

It is a cyclic number.

It is not a de Polignac number, because 221001221020061 - 2³⁸ = 220726343113117 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (221001221020861) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 110500610510030 + 110500610510031.

It is an arithmetic number, because the mean of its divisors is an integer number (110500610510031).

Almost surely, 2^{221001221020061} is an apocalyptic number.

It is an amenable number.

221001221020061 is a deficient number, since it is larger than the sum of its proper divisors (1).

221001221020061 is an equidigital number, since it uses as much as digits as its factorization.

221001221020061 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 192, while the sum is 20.

Adding to 221001221020061 its reverse (160020122100122), we get a palindrome (381021343120183).

The spelling of 221001221020061 in words is "two hundred twenty-one trillion, one billion, two hundred twenty-one million, twenty thousand, sixty-one".