155131228 has 48 divisors (see below), whose sum is σ = 326269440. Its totient is φ = 63100224.

The previous prime is 155131213. The next prime is 155131231. The reversal of 155131228 is 822131551.

It is a Harshad number since it is a multiple of its sum of digits (28).

It is a junction number, because it is equal to n+sod(n) for n = 155131196 and 155131205.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 88650 + ... + 90382.

It is an arithmetic number, because the mean of its divisors is an integer number (6797280).

Almost surely, 2^155131228 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 155131228, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (163134720).

155131228 is an abundant number, since it is smaller than the sum of its proper divisors (171138212).

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

155131228 is a wasteful number, since it uses less digits than its factorization.

155131228 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1906 (or 1904 counting only the distinct ones).

The product of its digits is 2400, while the sum is 28.

The square root of 155131228 is about 12455.1687262759. The cubic root of 155131228 is about 537.3200874697.

Adding to 155131228 its reverse (822131551), we get a palindrome (977262779).

The spelling of 155131228 in words is "one hundred fifty-five million, one hundred thirty-one thousand, two hundred twenty-eight".