155421355302225 has 60 divisors (see below), whose sum is σ = 290862056452044. Its totient is φ = 82036838983680.

The previous prime is 155421355302221. The next prime is 155421355302253. The reversal of 155421355302225 is 522203553124551.

155421355302225 is a `hidden beast` number, since 1 + 5 + 5 + 42 + 1 + 35 + 530 + 22 + 25 = 666.

It can be written as a sum of positive squares in 6 ways, for example, as 23590565568144 + 131830789734081 = 4857012^2 + 11481759^2 .

It is not a de Polignac number, because 155421355302225 - 2² = 155421355302221 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (45).

It is not an unprimeable number, because it can be changed into a prime (155421355302221) by changing a digit.

It is a polite number, since it can be written in 59 ways as a sum of consecutive naturals, for example, 395428764 + ... + 395821613.

Almost surely, 2^{155421355302225} is an apocalyptic number.

155421355302225 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

It is an amenable number.

155421355302225 is a deficient number, since it is larger than the sum of its proper divisors (135440701149819).

155421355302225 is an equidigital number, since it uses as much as digits as its factorization.

155421355302225 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 791250496 (or 791250482 counting only the distinct ones).

The product of its (nonzero) digits is 1800000, while the sum is 45.

The spelling of 155421355302225 in words is "one hundred fifty-five trillion, four hundred twenty-one billion, three hundred fifty-five million, three hundred two thousand, two hundred twenty-five".