1212200101891 has 2 divisors, whose sum is σ = 1212200101892. Its totient is φ = 1212200101890.

The previous prime is 1212200101823. The next prime is 1212200101949. The reversal of 1212200101891 is 1981010022121.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 1212200101891 - 2¹¹ = 1212200099843 is a prime.

It is not a weakly prime, because it can be changed into another prime (1212200101991) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 606100050945 + 606100050946.

It is an arithmetic number, because the mean of its divisors is an integer number (606100050946).

Almost surely, 2^{1212200101891} is an apocalyptic number.

1212200101891 is a deficient number, since it is larger than the sum of its proper divisors (1).

1212200101891 is an equidigital number, since it uses as much as digits as its factorization.

1212200101891 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 576, while the sum is 28.

The spelling of 1212200101891 in words is "one trillion, two hundred twelve billion, two hundred million, one hundred one thousand, eight hundred ninety-one".