842519221 has 2 divisors, whose sum is σ = 842519222. Its totient is φ = 842519220.

The previous prime is 842519213. The next prime is 842519239. The reversal of 842519221 is 122915248.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 836944900 + 5574321 = 28930^2 + 2361^2 .

It is a cyclic number.

It is not a de Polignac number, because 842519221 - 2³ = 842519213 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (842519621) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 421259610 + 421259611.

It is an arithmetic number, because the mean of its divisors is an integer number (421259611).

Almost surely, 2^842519221 is an apocalyptic number.

It is an amenable number.

842519221 is a deficient number, since it is larger than the sum of its proper divisors (1).

842519221 is an equidigital number, since it uses as much as digits as its factorization.

842519221 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 11520, while the sum is 34.

The square root of 842519221 is about 29026.1816469201. The cubic root of 842519221 is about 944.4811017985.

The spelling of 842519221 in words is "eight hundred forty-two million, five hundred nineteen thousand, two hundred twenty-one".