842577121 has 2 divisors, whose sum is σ = 842577122. Its totient is φ = 842577120.

The previous prime is 842577119. The next prime is 842577139. The reversal of 842577121 is 121775248.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 545876496 + 296700625 = 23364^2 + 17225^2 .

It is a cyclic number.

It is not a de Polignac number, because 842577121 - 2¹ = 842577119 is a prime.

Together with 842577119, it forms a pair of twin primes.

It is not a weakly prime, because it can be changed into another prime (842577161) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 421288560 + 421288561.

It is an arithmetic number, because the mean of its divisors is an integer number (421288561).

Almost surely, 2^842577121 is an apocalyptic number.

It is an amenable number.

842577121 is a deficient number, since it is larger than the sum of its proper divisors (1).

842577121 is an equidigital number, since it uses as much as digits as its factorization.

842577121 is an evil number, because the sum of its binary digits is even.

The product of its digits is 31360, while the sum is 37.

The square root of 842577121 is about 29027.1790052013. The cubic root of 842577121 is about 944.5027369936.

It can be divided in two parts, 84257 and 7121, that added together give a triangular number (91378 = T₄₂₇).

The spelling of 842577121 in words is "eight hundred forty-two million, five hundred seventy-seven thousand, one hundred twenty-one".