206756420161 has 4 divisors (see below), whose sum is σ = 206758126512. Its totient is φ = 206754713812.

The previous prime is 206756420153. The next prime is 206756420177. The reversal of 206756420161 is 161024657602.

It is a happy number.

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, and also an emirpimes, since its reverse is a distinct semiprime: 161024657602 = 2 ⋅80512328801.

It is a cyclic number.

It is not a de Polignac number, because 206756420161 - 2³ = 206756420153 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (206756420111) 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, 656275 + ... + 918808.

It is an arithmetic number, because the mean of its divisors is an integer number (51689531628).

Almost surely, 2^206756420161 is an apocalyptic number.

It is an amenable number.

206756420161 is a deficient number, since it is larger than the sum of its proper divisors (1706351).

206756420161 is a wasteful number, since it uses less digits than its factorization.

206756420161 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1706350.

The product of its (nonzero) digits is 120960, while the sum is 40.

The spelling of 206756420161 in words is "two hundred six billion, seven hundred fifty-six million, four hundred twenty thousand, one hundred sixty-one".