155221146 has 48 divisors (see below), whose sum is σ = 357739200. Its totient is φ = 48501504.

The previous prime is 155221133. The next prime is 155221159. The reversal of 155221146 is 641122551.

It is an interprime number because it is at equal distance from previous prime (155221133) and next prime (155221159).

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 30835 + ... + 35513.

It is an arithmetic number, because the mean of its divisors is an integer number (7452900).

Almost surely, 2^155221146 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 155221146, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (178869600).

155221146 is an abundant number, since it is smaller than the sum of its proper divisors (202518054).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

155221146 is a wasteful number, since it uses less digits than its factorization.

155221146 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4803 (or 4800 counting only the distinct ones).

The product of its digits is 2400, while the sum is 27.

The square root of 155221146 is about 12458.7778694381. Note that the first 3 decimals coincide. The cubic root of 155221146 is about 537.4238822083.

Adding to 155221146 its reverse (641122551), we get a palindrome (796343697).

The spelling of 155221146 in words is "one hundred fifty-five million, two hundred twenty-one thousand, one hundred forty-six".