155421231056 has 80 divisors (see below), whose sum is σ = 370905427200. Its totient is φ = 61437947904.

The previous prime is 155421231011. The next prime is 155421231071. The reversal of 155421231056 is 650132124551.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1880000 + ... + 1960928.

It is an arithmetic number, because the mean of its divisors is an integer number (4636317840).

Almost surely, 2^155421231056 is an apocalyptic number.

155421231056 is a gapful number since it is divisible by the number (16) 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 155421231056, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (185452713600).

155421231056 is an abundant number, since it is smaller than the sum of its proper divisors (215484196144).

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

155421231056 is a wasteful number, since it uses less digits than its factorization.

155421231056 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 82276 (or 82270 counting only the distinct ones).

The product of its (nonzero) digits is 36000, while the sum is 35.

The spelling of 155421231056 in words is "one hundred fifty-five billion, four hundred twenty-one million, two hundred thirty-one thousand, fifty-six".