2155178078 has 8 divisors (see below), whose sum is σ = 3287559960. Its totient is φ = 1059324760.

The previous prime is 2155178023. The next prime is 2155178101. The reversal of 2155178078 is 8708715512.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 9131993 + ... + 9132228.

It is an arithmetic number, because the mean of its divisors is an integer number (410944995).

Almost surely, 2^2155178078 is an apocalyptic number.

2155178078 is a deficient number, since it is larger than the sum of its proper divisors (1132381882).

2155178078 is a wasteful number, since it uses less digits than its factorization.

2155178078 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 18264282.

The product of its (nonzero) digits is 156800, while the sum is 44.

The square root of 2155178078 is about 46423.8955495982. The cubic root of 2155178078 is about 1291.6981977254.

The spelling of 2155178078 in words is "two billion, one hundred fifty-five million, one hundred seventy-eight thousand, seventy-eight".