7620766209 has 27 divisors (see below), whose sum is σ = 12808041987. Its totient is φ = 4353675984.

The previous prime is 7620766201. The next prime is 7620766271. The reversal of 7620766209 is 9026670267.

The square root of 7620766209 is 87297.

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., 3469799025 + 4150967184 = 58905^2 + 64428^2 .

It is not a de Polignac number, because 7620766209 - 2³ = 7620766201 is a prime.

It is a super-2 number, since 2×7620766209² (a number of 21 digits) contains 22 as substring.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (7620766201) by changing a digit.

It is a polite number, since it can be written in 26 ways as a sum of consecutive naturals, for example, 1831159 + ... + 1835315.

Almost surely, 2^7620766209 is an apocalyptic number.

7620766209 is the 87297-th square number.

7620766209 is the 43649-th centered octagonal number.

It is an amenable number.

7620766209 is a deficient number, since it is larger than the sum of its proper divisors (5187275778).

7620766209 is an frugal number, since it uses more digits than its factorization.

7620766209 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8334 (or 4167 counting only the distinct ones).

The product of its (nonzero) digits is 381024, while the sum is 45.

The cubic root of 7620766209 is about 1967.8842332569.

The spelling of 7620766209 in words is "seven billion, six hundred twenty million, seven hundred sixty-six thousand, two hundred nine".