204240645551 has 8 divisors (see below), whose sum is σ = 210834259584. Its totient is φ = 197647356960.

The previous prime is 204240645529. The next prime is 204240645569. The reversal of 204240645551 is 155546042402.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 204240645551 - 2⁶ = 204240645487 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 (204240645451) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 2312561 + ... + 2399253.

It is an arithmetic number, because the mean of its divisors is an integer number (26354282448).

Almost surely, 2^204240645551 is an apocalyptic number.

204240645551 is a deficient number, since it is larger than the sum of its proper divisors (6593614033).

204240645551 is an equidigital number, since it uses as much as digits as its factorization.

204240645551 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 162721.

The product of its (nonzero) digits is 192000, while the sum is 38.

Adding to 204240645551 its reverse (155546042402), we get a palindrome (359786687953).

The spelling of 204240645551 in words is "two hundred four billion, two hundred forty million, six hundred forty-five thousand, five hundred fifty-one".