206611111157 has 4 divisors (see below), whose sum is σ = 225393939456. Its totient is φ = 187828282860.

The previous prime is 206611111121. The next prime is 206611111207. The reversal of 206611111157 is 751111116602.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 206611111157 - 2²² = 206606916853 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (206611111457) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 9391414133 + ... + 9391414154.

It is an arithmetic number, because the mean of its divisors is an integer number (56348484864).

Almost surely, 2^206611111157 is an apocalyptic number.

It is an amenable number.

206611111157 is a deficient number, since it is larger than the sum of its proper divisors (18782828299).

206611111157 is a wasteful number, since it uses less digits than its factorization.

206611111157 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 18782828298.

The product of its (nonzero) digits is 2520, while the sum is 32.

Adding to 206611111157 its reverse (751111116602), we get a palindrome (957722227759).

Subtracting 206611111157 from its reverse (751111116602), we obtain a palindrome (544500005445).

The spelling of 206611111157 in words is "two hundred six billion, six hundred eleven million, one hundred eleven thousand, one hundred fifty-seven".