2127505208409 has 27 divisors (see below), whose sum is σ = 3574839131487. Its totient is φ = 1215699758784.

The previous prime is 2127505208407. The next prime is 2127505208447. The reversal of 2127505208409 is 9048025057212.

The square root of 2127505208409 is 1458597.

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

2127505208409 is a `hidden beast` number, since 2 + 12 + 75 + 0 + 520 + 8 + 40 + 9 = 666.

It can be written as a sum of positive squares in only one way, i.e., 250955912025 + 1876549296384 = 500955^2 + 1369872^2 .

It is not a de Polignac number, because 2127505208409 - 2¹ = 2127505208407 is a prime.

It is a super-2 number, since 2×2127505208409² (a number of 25 digits) contains 22 as substring.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (2127505208407) 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, 30595809 + ... + 30665265.

Almost surely, 2^{2127505208409} is an apocalyptic number.

2127505208409 is the 1458597-th square number.

2127505208409 is the 729299-th centered octagonal number.

It is an amenable number.

2127505208409 is a deficient number, since it is larger than the sum of its proper divisors (1447333923078).

2127505208409 is an frugal number, since it uses more digits than its factorization.

2127505208409 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 138934 (or 69467 counting only the distinct ones).

The product of its (nonzero) digits is 403200, while the sum is 45.

The spelling of 2127505208409 in words is "two trillion, one hundred twenty-seven billion, five hundred five million, two hundred eight thousand, four hundred nine".