204355543861 has 4 divisors (see below), whose sum is σ = 233549192992. Its totient is φ = 175161894732.

The previous prime is 204355543811. The next prime is 204355543883. The reversal of 204355543861 is 168345553402.

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.

It is a cyclic number.

It is not a de Polignac number, because 204355543861 - 2²¹ = 204353446709 is a prime.

It is a super-2 number, since 2×204355543861² (a number of 23 digits) contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (204355543811) 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, 14596824555 + ... + 14596824568.

It is an arithmetic number, because the mean of its divisors is an integer number (58387298248).

Almost surely, 2^204355543861 is an apocalyptic number.

It is an amenable number.

204355543861 is a deficient number, since it is larger than the sum of its proper divisors (29193649131).

204355543861 is an equidigital number, since it uses as much as digits as its factorization.

204355543861 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 29193649130.

The product of its (nonzero) digits is 1728000, while the sum is 46.

The spelling of 204355543861 in words is "two hundred four billion, three hundred fifty-five million, five hundred forty-three thousand, eight hundred sixty-one".