842626694809 has 9 divisors (see below), whose sum is σ = 889328021823. Its totient is φ = 798261398352.

The previous prime is 842626694797. The next prime is 842626694831. The reversal of 842626694809 is 908496626248.

The square root of 842626694809 is 917947.

It is a perfect power (a square), and thus also a powerful number.

It can be written as a sum of positive squares in only one way, i.e., 233177923225 + 609448771584 = 482885^2 + 780672^2 .

It is not a de Polignac number, because 842626694809 - 2⁹ = 842626694297 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (842626664809) by changing a digit.

It is a polite number, since it can be written in 8 ways as a sum of consecutive naturals, for example, 17416837 + ... + 17465149.

It is an arithmetic number, because the mean of its divisors is an integer number (98814224647).

Almost surely, 2^842626694809 is an apocalyptic number.

842626694809 is the 917947-th square number.

842626694809 is the 458974-th centered octagonal number.

It is an amenable number.

842626694809 is a deficient number, since it is larger than the sum of its proper divisors (46701327014).

842626694809 is an frugal number, since it uses more digits than its factorization.

842626694809 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 96664 (or 48332 counting only the distinct ones).

The product of its (nonzero) digits is 71663616, while the sum is 64.

Multiplying 842626694809 by its sum of digits (64), we get a square (53928108467776 = 7343576²).

The spelling of 842626694809 in words is "eight hundred forty-two billion, six hundred twenty-six million, six hundred ninety-four thousand, eight hundred nine".