155215223176420 has 144 divisors (see below), whose sum is σ = 365389273347840. Its totient is φ = 54925828876800.

The previous prime is 155215223176399. The next prime is 155215223176501. The reversal of 155215223176420 is 24671322512551.

It is an unprimeable number.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 109533376 + ... + 110941384.

It is an arithmetic number, because the mean of its divisors is an integer number (2537425509360).

Almost surely, 2^{155215223176420} is an apocalyptic number.

155215223176420 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 155215223176420, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (182694636673920).

155215223176420 is an abundant number, since it is smaller than the sum of its proper divisors (210174050171420).

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

155215223176420 is a wasteful number, since it uses less digits than its factorization.

155215223176420 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1408386 (or 1408341 counting only the distinct ones).

The product of its (nonzero) digits is 1008000, while the sum is 46.

Adding to 155215223176420 its reverse (24671322512551), we get a palindrome (179886545688971).

The spelling of 155215223176420 in words is "one hundred fifty-five trillion, two hundred fifteen billion, two hundred twenty-three million, one hundred seventy-six thousand, four hundred twenty".