1001221101977 has 2 divisors, whose sum is σ = 1001221101978. Its totient is φ = 1001221101976.

The previous prime is 1001221101961. The next prime is 1001221102009. The reversal of 1001221101977 is 7791011221001.

It is a happy number.

It is an a-pointer prime, because the next prime (1001221102009) can be obtained adding 1001221101977 to its sum of digits (32).

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 613560456601 + 387660645376 = 783301^2 + 622624^2 .

It is a cyclic number.

It is not a de Polignac number, because 1001221101977 - 2⁴ = 1001221101961 is a prime.

It is not a weakly prime, because it can be changed into another prime (1001221101677) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 500610550988 + 500610550989.

It is an arithmetic number, because the mean of its divisors is an integer number (500610550989).

Almost surely, 2^{1001221101977} is an apocalyptic number.

It is an amenable number.

1001221101977 is a deficient number, since it is larger than the sum of its proper divisors (1).

1001221101977 is an equidigital number, since it uses as much as digits as its factorization.

1001221101977 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 1764, while the sum is 32.

Adding to 1001221101977 its reverse (7791011221001), we get a palindrome (8792232322978).

The spelling of 1001221101977 in words is "one trillion, one billion, two hundred twenty-one million, one hundred one thousand, nine hundred seventy-seven".