221656434032381 has 2 divisors, whose sum is σ = 221656434032382. Its totient is φ = 221656434032380.

The previous prime is 221656434032351. The next prime is 221656434032419. The reversal of 221656434032381 is 183230434656122.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 149111183009881 + 72545251022500 = 12211109^2 + 8517350^2 .

It is a cyclic number.

It is not a de Polignac number, because 221656434032381 - 2³⁰ = 221655360290557 is a prime.

It is a super-2 number, since 2×221656434032381² (a number of 29 digits) contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (221656434032351) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 110828217016190 + 110828217016191.

It is an arithmetic number, because the mean of its divisors is an integer number (110828217016191).

Almost surely, 2^{221656434032381} is an apocalyptic number.

It is an amenable number.

221656434032381 is a deficient number, since it is larger than the sum of its proper divisors (1).

221656434032381 is an equidigital number, since it uses as much as digits as its factorization.

221656434032381 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 4976640, while the sum is 50.

The spelling of 221656434032381 in words is "two hundred twenty-one trillion, six hundred fifty-six billion, four hundred thirty-four million, thirty-two thousand, three hundred eighty-one".