2157215378 has 8 divisors (see below), whose sum is σ = 3236209200. Its totient is φ = 1078478980.

The previous prime is 2157215351. The next prime is 2157215393. The reversal of 2157215378 is 8735127512.

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

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 41828 + ... + 77871.

It is an arithmetic number, because the mean of its divisors is an integer number (404526150).

Almost surely, 2^2157215378 is an apocalyptic number.

2157215378 is a deficient number, since it is larger than the sum of its proper divisors (1078993822).

2157215378 is a wasteful number, since it uses less digits than its factorization.

2157215378 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 128712.

The product of its digits is 117600, while the sum is 41.

The square root of 2157215378 is about 46445.8327301815. The cubic root of 2157215378 is about 1292.1050856737.

The spelling of 2157215378 in words is "two billion, one hundred fifty-seven million, two hundred fifteen thousand, three hundred seventy-eight".