155404240 has 80 divisors (see below), whose sum is σ = 375975936. Its totient is φ = 59673600.

The previous prime is 155404219. The next prime is 155404241. The reversal of 155404240 is 42404551.

It is a happy number.

It is a tau number, because it is divible by the number of its divisors (80).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (155404241) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 552900 + ... + 553180.

Almost surely, 2^155404240 is an apocalyptic number.

155404240 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 155404240, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (187987968).

155404240 is an abundant number, since it is smaller than the sum of its proper divisors (220571696).

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

155404240 is a wasteful number, since it uses less digits than its factorization.

155404240 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 548 (or 542 counting only the distinct ones).

The product of its (nonzero) digits is 3200, while the sum is 25.

The square root of 155404240 is about 12466.1236958407. The cubic root of 155404240 is about 537.6351086352.

Adding to 155404240 its reverse (42404551), we get a palindrome (197808791).

The spelling of 155404240 in words is "one hundred fifty-five million, four hundred four thousand, two hundred forty".