1221200019953 has 2 divisors, whose sum is σ = 1221200019954. Its totient is φ = 1221200019952.

The previous prime is 1221200019931. The next prime is 1221200020009. The reversal of 1221200019953 is 3599100021221.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 717735979249 + 503464040704 = 847193^2 + 709552^2 .

It is a cyclic number.

It is not a de Polignac number, because 1221200019953 - 2²⁴ = 1221183242737 is a prime.

It is a Sophie Germain prime.

It is a Curzon number.

It is not a weakly prime, because it can be changed into another prime (1221200019353) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 610600009976 + 610600009977.

It is an arithmetic number, because the mean of its divisors is an integer number (610600009977).

Almost surely, 2^{1221200019953} is an apocalyptic number.

It is an amenable number.

1221200019953 is a deficient number, since it is larger than the sum of its proper divisors (1).

1221200019953 is an equidigital number, since it uses as much as digits as its factorization.

1221200019953 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 9720, while the sum is 35.

The spelling of 1221200019953 in words is "one trillion, two hundred twenty-one billion, two hundred million, nineteen thousand, nine hundred fifty-three".