613161221 has 2 divisors, whose sum is σ = 613161222. Its totient is φ = 613161220.

The previous prime is 613161149. The next prime is 613161229. The reversal of 613161221 is 122161316.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 356680996 + 256480225 = 18886^2 + 16015^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-613161221 is a prime.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (613161229) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 306580610 + 306580611.

It is an arithmetic number, because the mean of its divisors is an integer number (306580611).

Almost surely, 2^613161221 is an apocalyptic number.

It is an amenable number.

613161221 is a deficient number, since it is larger than the sum of its proper divisors (1).

613161221 is an equidigital number, since it uses as much as digits as its factorization.

613161221 is an evil number, because the sum of its binary digits is even.

The product of its digits is 432, while the sum is 23.

The square root of 613161221 is about 24762.0924196644. The cubic root of 613161221 is about 849.5551171350. Note that the first 3 decimals are identical.

The spelling of 613161221 in words is "six hundred thirteen million, one hundred sixty-one thousand, two hundred twenty-one".