155355454221 has 16 divisors (see below), whose sum is σ = 226122995520. Its totient is φ = 94091726720.

The previous prime is 155355454201. The next prime is 155355454229. The reversal of 155355454221 is 122454553551.

It is a happy number.

It is a cyclic number.

It is not a de Polignac number, because 155355454221 - 2¹⁸ = 155355192077 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (155355454229) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1527336 + ... + 1625873.

It is an arithmetic number, because the mean of its divisors is an integer number (14132687220).

Almost surely, 2^155355454221 is an apocalyptic number.

155355454221 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

It is an amenable number.

155355454221 is a deficient number, since it is larger than the sum of its proper divisors (70767541299).

155355454221 is a wasteful number, since it uses less digits than its factorization.

155355454221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3154716.

The product of its digits is 600000, while the sum is 42.

The spelling of 155355454221 in words is "one hundred fifty-five billion, three hundred fifty-five million, four hundred fifty-four thousand, two hundred twenty-one".