2155121578830 has 128 divisors (see below), whose sum is σ = 6077756768256. Its totient is φ = 483617692800.

The previous prime is 2155121578787. The next prime is 2155121578867. The reversal of 2155121578830 is 388751215512.

It is a self number, because there is not a number n which added to its sum of digits gives 2155121578830.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 4344424 + ... + 4815003.

It is an arithmetic number, because the mean of its divisors is an integer number (47482474752).

Almost surely, 2^{2155121578830} is an apocalyptic number.

2155121578830 is an abundant number, since it is smaller than the sum of its proper divisors (3922635189426).

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

2155121578830 is a wasteful number, since it uses less digits than its factorization.

2155121578830 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9159502.

The product of its (nonzero) digits is 672000, while the sum is 48.

The spelling of 2155121578830 in words is "two trillion, one hundred fifty-five billion, one hundred twenty-one million, five hundred seventy-eight thousand, eight hundred thirty".