206573138 has 6 divisors (see below), whose sum is σ = 309890199. Its totient is φ = 103276406.

The previous prime is 206573123. The next prime is 206573141. The reversal of 206573138 is 831375602.

It can be written as a sum of positive squares in only one way, i.e., 103286569 + 103286569 = 10163^2 + 10163^2 .

It is an ABA number since it can be written as A⋅B^A, here for A=2, B=10163.

It is a super-2 number, since 2×206573138² = 85344922686334088, which contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 206573098 and 206573107.

It is an unprimeable number.

It is a polite number, since it can be written in 2 ways as a sum of consecutive naturals, for example, 15245 + ... + 25407.

Almost surely, 2^206573138 is an apocalyptic number.

206573138 is a deficient number, since it is larger than the sum of its proper divisors (103317061).

206573138 is an frugal number, since it uses more digits than its factorization.

206573138 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 20328 (or 10165 counting only the distinct ones).

The product of its (nonzero) digits is 30240, while the sum is 35.

The square root of 206573138 is about 14372.6524343978. The cubic root of 206573138 is about 591.1412727018.

The spelling of 206573138 in words is "two hundred six million, five hundred seventy-three thousand, one hundred thirty-eight".