204421645155 has 64 divisors (see below), whose sum is σ = 406315865088. Its totient is φ = 85455198720.

The previous prime is 204421645151. The next prime is 204421645159. The reversal of 204421645155 is 551546124402.

It is an interprime number because it is at equal distance from previous prime (204421645151) and next prime (204421645159).

It is not a de Polignac number, because 204421645155 - 2² = 204421645151 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (39).

It is not an unprimeable number, because it can be changed into a prime (204421645151) by changing a digit.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 553756 + ... + 845865.

It is an arithmetic number, because the mean of its divisors is an integer number (6348685392).

Almost surely, 2^204421645155 is an apocalyptic number.

204421645155 is a deficient number, since it is larger than the sum of its proper divisors (201894219933).

204421645155 is a wasteful number, since it uses less digits than its factorization.

204421645155 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1399756.

The product of its (nonzero) digits is 192000, while the sum is 39.

Adding to 204421645155 its reverse (551546124402), we get a palindrome (755967769557).

The spelling of 204421645155 in words is "two hundred four billion, four hundred twenty-one million, six hundred forty-five thousand, one hundred fifty-five".