221297661544937 has 2 divisors, whose sum is σ = 221297661544938. Its totient is φ = 221297661544936.

The previous prime is 221297661544819. The next prime is 221297661545003. The reversal of 221297661544937 is 739445166792122.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 214927797293056 + 6369864251881 = 14660416^2 + 2523859^2 .

It is a cyclic number.

It is not a de Polignac number, because 221297661544937 - 2¹⁴ = 221297661528553 is a prime.

It is not a weakly prime, because it can be changed into another prime (221297661504937) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 110648830772468 + 110648830772469.

It is an arithmetic number, because the mean of its divisors is an integer number (110648830772469).

Almost surely, 2^{221297661544937} is an apocalyptic number.

It is an amenable number.

221297661544937 is a deficient number, since it is larger than the sum of its proper divisors (1).

221297661544937 is an equidigital number, since it uses as much as digits as its factorization.

221297661544937 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 274337280, while the sum is 68.

The spelling of 221297661544937 in words is "two hundred twenty-one trillion, two hundred ninety-seven billion, six hundred sixty-one million, five hundred forty-four thousand, nine hundred thirty-seven".