155504232033221 has 8 divisors (see below), whose sum is σ = 157866216505920. Its totient is φ = 153143454201408.

The previous prime is 155504232033187. The next prime is 155504232033263. The reversal of 155504232033221 is 122330232405551.

155504232033221 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

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

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-155504232033221 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 (155504235033221) 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, 301400516 + ... + 301916013.

It is an arithmetic number, because the mean of its divisors is an integer number (19733277063240).

Almost surely, 2^{155504232033221} is an apocalyptic number.

It is an amenable number.

155504232033221 is a deficient number, since it is larger than the sum of its proper divisors (2361984472699).

155504232033221 is an equidigital number, since it uses as much as digits as its factorization.

155504232033221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 603320443.

The product of its (nonzero) digits is 216000, while the sum is 38.

Adding to 155504232033221 its reverse (122330232405551), we get a palindrome (277834464438772).

The spelling of 155504232033221 in words is "one hundred fifty-five trillion, five hundred four billion, two hundred thirty-two million, thirty-three thousand, two hundred twenty-one".