243155550 has 72 divisors (see below), whose sum is σ = 662879448. Its totient is φ = 58942400.

The previous prime is 243155509. The next prime is 243155551. The reversal of 243155550 is 55551342.

It is a happy number.

It is a Harshad number since it is a multiple of its sum of digits (30).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (243155551) by changing a digit.

It is a polite number, since it can be written in 35 ways as a sum of consecutive naturals, for example, 11452 + ... + 24848.

It is an arithmetic number, because the mean of its divisors is an integer number (9206659).

Almost surely, 2^243155550 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 243155550, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (331439724).

243155550 is an abundant number, since it is smaller than the sum of its proper divisors (419723898).

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

243155550 is a wasteful number, since it uses less digits than its factorization.

243155550 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 13434 (or 13418 counting only the distinct ones).

The product of its (nonzero) digits is 15000, while the sum is 30.

The square root of 243155550 is about 15593.4457385146. The cubic root of 243155550 is about 624.1582695594.

The spelling of 243155550 in words is "two hundred forty-three million, one hundred fifty-five thousand, five hundred fifty".