842661397 has 4 divisors (see below), whose sum is σ = 863214156. Its totient is φ = 822108640.

The previous prime is 842661367. The next prime is 842661431. The reversal of 842661397 is 793166248.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 297252081 + 545409316 = 17241^2 + 23354^2 .

It is a cyclic number.

It is not a de Polignac number, because 842661397 - 2⁷ = 842661269 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (842661367) 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 in 3 ways as a sum of consecutive naturals, for example, 10276318 + ... + 10276399.

It is an arithmetic number, because the mean of its divisors is an integer number (215803539).

Almost surely, 2^842661397 is an apocalyptic number.

It is an amenable number.

842661397 is a deficient number, since it is larger than the sum of its proper divisors (20552759).

842661397 is a wasteful number, since it uses less digits than its factorization.

842661397 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 20552758.

The product of its digits is 435456, while the sum is 46.

The square root of 842661397 is about 29028.6306428671. The cubic root of 842661397 is about 944.5342262017.

The spelling of 842661397 in words is "eight hundred forty-two million, six hundred sixty-one thousand, three hundred ninety-seven".