2001221101949 has 2 divisors, whose sum is σ = 2001221101950. Its totient is φ = 2001221101948.

The previous prime is 2001221101909. The next prime is 2001221101987. The reversal of 2001221101949 is 9491011221002.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 1222114773049 + 779106328900 = 1105493^2 + 882670^2 .

It is a cyclic number.

It is not a de Polignac number, because 2001221101949 - 2¹⁶ = 2001221036413 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (2001221101909) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1000610550974 + 1000610550975.

It is an arithmetic number, because the mean of its divisors is an integer number (1000610550975).

Almost surely, 2^{2001221101949} is an apocalyptic number.

It is an amenable number.

2001221101949 is a deficient number, since it is larger than the sum of its proper divisors (1).

2001221101949 is an equidigital number, since it uses as much as digits as its factorization.

2001221101949 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 2592, while the sum is 32.

The spelling of 2001221101949 in words is "two trillion, one billion, two hundred twenty-one million, one hundred one thousand, nine hundred forty-nine".