155531320 has 64 divisors (see below), whose sum is σ = 401863680. Its totient is φ = 53068416.

The previous prime is 155531287. The next prime is 155531323. The reversal of 155531320 is 23135551.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (155531323) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 62337 + ... + 64783.

It is an arithmetic number, because the mean of its divisors is an integer number (6279120).

Almost surely, 2^155531320 is an apocalyptic number.

155531320 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 155531320, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (200931840).

155531320 is an abundant number, since it is smaller than the sum of its proper divisors (246332360).

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

155531320 is a wasteful number, since it uses less digits than its factorization.

155531320 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2692 (or 2688 counting only the distinct ones).

The product of its (nonzero) digits is 2250, while the sum is 25.

The square root of 155531320 is about 12471.2196676989. The cubic root of 155531320 is about 537.7816169817.

Adding to 155531320 its reverse (23135551), we get a palindrome (178666871).

The spelling of 155531320 in words is "one hundred fifty-five million, five hundred thirty-one thousand, three hundred twenty".