623709801009 has 27 divisors (see below), whose sum is σ = 918418165483. Its totient is φ = 407878993392.

The previous prime is 623709800963. The next prime is 623709801019. The reversal of 623709801009 is 900108907326.

The square root of 623709801009 is 789753.

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

623709801009 is a `hidden beast` number, since 623 + 7 + 0 + 9 + 8 + 0 + 10 + 0 + 9 = 666.

It can be written as a sum of positive squares in only one way, i.e., 449630597025 + 174079203984 = 670545^2 + 417228^2 .

It is not a de Polignac number, because 623709801009 - 2⁷ = 623709800881 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (623709801019) 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, 125568244 + ... + 125573210.

Almost surely, 2^623709801009 is an apocalyptic number.

623709801009 is the 789753-rd square number.

623709801009 is the 394877-th centered octagonal number.

It is an amenable number.

623709801009 is a deficient number, since it is larger than the sum of its proper divisors (294708364474).

623709801009 is an frugal number, since it uses more digits than its factorization.

623709801009 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10046 (or 5023 counting only the distinct ones).

The product of its (nonzero) digits is 163296, while the sum is 45.

The spelling of 623709801009 in words is "six hundred twenty-three billion, seven hundred nine million, eight hundred one thousand, nine".