155421140 has 144 divisors (see below), whose sum is σ = 424025280. Its totient is φ = 47416320.

The previous prime is 155421137. The next prime is 155421187. The reversal of 155421140 is 41124551.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 316295 + ... + 316785.

It is an arithmetic number, because the mean of its divisors is an integer number (2944620).

Almost surely, 2^155421140 is an apocalyptic number.

155421140 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 155421140, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (212012640).

155421140 is an abundant number, since it is smaller than the sum of its proper divisors (268604140).

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

155421140 is a wasteful number, since it uses less digits than its factorization.

155421140 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 550 (or 541 counting only the distinct ones).

The product of its (nonzero) digits is 800, while the sum is 23.

The square root of 155421140 is about 12466.8015144222. The cubic root of 155421140 is about 537.6545969580.

Adding to 155421140 its reverse (41124551), we get a palindrome (196545691).

The spelling of 155421140 in words is "one hundred fifty-five million, four hundred twenty-one thousand, one hundred forty".