221331013 has 2 divisors, whose sum is σ = 221331014. Its totient is φ = 221331012.

The previous prime is 221330971. The next prime is 221331029. The reversal of 221331013 is 310133122.

221331013 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is an a-pointer prime, because the next prime (221331029) can be obtained adding 221331013 to its sum of digits (16).

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 190495204 + 30835809 = 13802^2 + 5553^2 .

It is a cyclic number.

It is not a de Polignac number, because 221331013 - 2¹⁷ = 221199941 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (221331043) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 110665506 + 110665507.

It is an arithmetic number, because the mean of its divisors is an integer number (110665507).

Almost surely, 2^221331013 is an apocalyptic number.

It is an amenable number.

221331013 is a deficient number, since it is larger than the sum of its proper divisors (1).

221331013 is an equidigital number, since it uses as much as digits as its factorization.

221331013 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 108, while the sum is 16.

The square root of 221331013 is about 14877.1977536094. The cubic root of 221331013 is about 604.8960621028.

Adding to 221331013 its reverse (310133122), we get a palindrome (531464135).

The spelling of 221331013 in words is "two hundred twenty-one million, three hundred thirty-one thousand, thirteen".