155023440 has 160 divisors (see below), whose sum is σ = 564713856. Its totient is φ = 34682880.

The previous prime is 155023417. The next prime is 155023441. The reversal of 155023440 is 44320551.

It is a Harshad number since it is a multiple of its sum of digits (24).

It is a self number, because there is not a number n which added to its sum of digits gives 155023440.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (155023441) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 32062 + ... + 36578.

Almost surely, 2^155023440 is an apocalyptic number.

155023440 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 155023440, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (282356928).

155023440 is an abundant number, since it is smaller than the sum of its proper divisors (409690416).

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

155023440 is a wasteful number, since it uses less digits than its factorization.

155023440 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4557 (or 4551 counting only the distinct ones).

The product of its (nonzero) digits is 2400, while the sum is 24.

The square root of 155023440 is about 12450.8409354549. The cubic root of 155023440 is about 537.1956120446.

Adding to 155023440 its reverse (44320551), we get a palindrome (199343991).

The spelling of 155023440 in words is "one hundred fifty-five million, twenty-three thousand, four hundred forty".