7138499209209 has 27 divisors (see below), whose sum is σ = 10654884263439. Its totient is φ = 4605323052960.

The previous prime is 7138499209201. The next prime is 7138499209211. The reversal of 7138499209209 is 9029029948317.

The square root of 7138499209209 is 2671797.

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

7138499209209 is a `hidden beast` number, since 7 + 1 + 38 + 499 + 20 + 92 + 0 + 9 = 666.

It can be written as a sum of positive squares in only one way, i.e., 2642403049209 + 4496096160000 = 1625547^2 + 2120400^2 .

It is not a de Polignac number, because 7138499209209 - 2³ = 7138499209201 is a prime.

It is not an unprimeable number, because it can be changed into a prime (7138499209201) 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, 248462757 + ... + 248491485.

Almost surely, 2^{7138499209209} is an apocalyptic number.

7138499209209 is the 2671797-th square number.

7138499209209 is the 1335899-th centered octagonal number.

It is an amenable number.

7138499209209 is a deficient number, since it is larger than the sum of its proper divisors (3516385054230).

7138499209209 is an frugal number, since it uses more digits than its factorization.

7138499209209 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 57526 (or 28763 counting only the distinct ones).

The product of its (nonzero) digits is 17635968, while the sum is 63.

The spelling of 7138499209209 in words is "seven trillion, one hundred thirty-eight billion, four hundred ninety-nine million, two hundred nine thousand, two hundred nine".