205672023405 has 24 divisors (see below), whose sum is σ = 356510938680. Its totient is φ = 109687818240.

The previous prime is 205672023341. The next prime is 205672023407. The reversal of 205672023405 is 504320276502.

205672023405 is a `hidden beast` number, since 205 + 6 + 7 + 20 + 23 + 405 = 666.

It can be written as a sum of positive squares in 4 ways, for example, as 617920164 + 205054103241 = 24858^2 + 452829^2 .

It is not a de Polignac number, because 205672023405 - 2⁶ = 205672023341 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 205672023405.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (205672023407) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 1543845 + ... + 1671765.

It is an arithmetic number, because the mean of its divisors is an integer number (14854622445).

Almost surely, 2^205672023405 is an apocalyptic number.

It is an amenable number.

205672023405 is a deficient number, since it is larger than the sum of its proper divisors (150838915275).

205672023405 is a wasteful number, since it uses less digits than its factorization.

205672023405 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 163661 (or 163658 counting only the distinct ones).

The product of its (nonzero) digits is 100800, while the sum is 36.

Adding to 205672023405 its reverse (504320276502), we get a palindrome (709992299907).

The spelling of 205672023405 in words is "two hundred five billion, six hundred seventy-two million, twenty-three thousand, four hundred five".