155021155 has 4 divisors (see below), whose sum is σ = 186025392. Its totient is φ = 124016920.

The previous prime is 155021107. The next prime is 155021159. The reversal of 155021155 is 551120551.

It is a semiprime because it is the product of two primes.

It is not a de Polignac number, because 155021155 - 2²³ = 146632547 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (155021159) 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 3 ways as a sum of consecutive naturals, for example, 15502111 + ... + 15502120.

It is an arithmetic number, because the mean of its divisors is an integer number (46506348).

Almost surely, 2^155021155 is an apocalyptic number.

155021155 is a deficient number, since it is larger than the sum of its proper divisors (31004237).

155021155 is an equidigital number, since it uses as much as digits as its factorization.

155021155 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 31004236.

The product of its (nonzero) digits is 1250, while the sum is 25.

The square root of 155021155 is about 12450.7491742465. The cubic root of 155021155 is about 537.1929726631.

The spelling of 155021155 in words is "one hundred fifty-five million, twenty-one thousand, one hundred fifty-five".