155500505 has 4 divisors (see below), whose sum is σ = 186600612. Its totient is φ = 124400400.

The previous prime is 155500489. The next prime is 155500507. The reversal of 155500505 is 505005551.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 505005551 = 149 ⋅3389299.

It can be written as a sum of positive squares in 2 ways, for example, as 120406729 + 35093776 = 10973^2 + 5924^2 .

It is not a de Polignac number, because 155500505 - 2⁴ = 155500489 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (155500507) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 15550046 + ... + 15550055.

It is an arithmetic number, because the mean of its divisors is an integer number (46650153).

Almost surely, 2^155500505 is an apocalyptic number.

It is an amenable number.

155500505 is a deficient number, since it is larger than the sum of its proper divisors (31100107).

155500505 is an equidigital number, since it uses as much as digits as its factorization.

155500505 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 31100106.

The product of its (nonzero) digits is 3125, while the sum is 26.

The square root of 155500505 is about 12469.9841619787. The cubic root of 155500505 is about 537.7460982298.

The spelling of 155500505 in words is "one hundred fifty-five million, five hundred thousand, five hundred five".