1221995805907 has 2 divisors, whose sum is σ = 1221995805908. Its totient is φ = 1221995805906.

The previous prime is 1221995805883. The next prime is 1221995805917. The reversal of 1221995805907 is 7095085991221.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 1221995805907 - 2³⁵ = 1187636067539 is a prime.

It is not a weakly prime, because it can be changed into another prime (1221995805917) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 610997902953 + 610997902954.

It is an arithmetic number, because the mean of its divisors is an integer number (610997902954).

Almost surely, 2^{1221995805907} is an apocalyptic number.

1221995805907 is a deficient number, since it is larger than the sum of its proper divisors (1).

1221995805907 is an equidigital number, since it uses as much as digits as its factorization.

1221995805907 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 4082400, while the sum is 58.

The spelling of 1221995805907 in words is "one trillion, two hundred twenty-one billion, nine hundred ninety-five million, eight hundred five thousand, nine hundred seven".