155221012240 has 480 divisors, whose sum is σ = 453426336000. Its totient is φ = 49123307520.

The previous prime is 155221012217. The next prime is 155221012253. The reversal of 155221012240 is 42210122551.

It is an unprimeable number.

It is a polite number, since it can be written in 95 ways as a sum of consecutive naturals, for example, 787923822 + ... + 787924018.

It is an arithmetic number, because the mean of its divisors is an integer number (944638200).

Almost surely, 2^155221012240 is an apocalyptic number.

155221012240 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 155221012240, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (226713168000).

155221012240 is an abundant number, since it is smaller than the sum of its proper divisors (298205323760).

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

155221012240 is a wasteful number, since it uses less digits than its factorization.

155221012240 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 463 (or 450 counting only the distinct ones).

The product of its (nonzero) digits is 1600, while the sum is 25.

Adding to 155221012240 its reverse (42210122551), we get a palindrome (197431134791).

The spelling of 155221012240 in words is "one hundred fifty-five billion, two hundred twenty-one million, twelve thousand, two hundred forty".