221038479397 has 2 divisors, whose sum is σ = 221038479398. Its totient is φ = 221038479396.

The previous prime is 221038479331. The next prime is 221038479419. The reversal of 221038479397 is 793974830122.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 144423560961 + 76614918436 = 380031^2 + 276794^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-221038479397 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (221038479307) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 110519239698 + 110519239699.

It is an arithmetic number, because the mean of its divisors is an integer number (110519239699).

Almost surely, 2^221038479397 is an apocalyptic number.

It is an amenable number.

221038479397 is a deficient number, since it is larger than the sum of its proper divisors (1).

221038479397 is an equidigital number, since it uses as much as digits as its factorization.

221038479397 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 4572288, while the sum is 55.

The spelling of 221038479397 in words is "two hundred twenty-one billion, thirty-eight million, four hundred seventy-nine thousand, three hundred ninety-seven".