2155845123 has 48 divisors (see below), whose sum is σ = 3437834400. Its totient is φ = 1295723520.

The previous prime is 2155845113. The next prime is 2155845137. The reversal of 2155845123 is 3215485512.

2155845123 is a `hidden beast` number, since 2 + 1 + 5 + 584 + 51 + 23 = 666.

It is not a de Polignac number, because 2155845123 - 2¹² = 2155841027 is a prime.

It is not an unprimeable number, because it can be changed into a prime (2155845113) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 579393 + ... + 583101.

It is an arithmetic number, because the mean of its divisors is an integer number (71621550).

Almost surely, 2^2155845123 is an apocalyptic number.

2155845123 is a deficient number, since it is larger than the sum of its proper divisors (1281989277).

2155845123 is a wasteful number, since it uses less digits than its factorization.

2155845123 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3892 (or 3889 counting only the distinct ones).

The product of its digits is 48000, while the sum is 36.

The square root of 2155845123 is about 46431.0792788623. The cubic root of 2155845123 is about 1291.8314476496.

The spelling of 2155845123 in words is "two billion, one hundred fifty-five million, eight hundred forty-five thousand, one hundred twenty-three".