2157214818 has 64 divisors (see below), whose sum is σ = 4984519680. Its totient is φ = 615528000.

The previous prime is 2157214777. The next prime is 2157214819. The reversal of 2157214818 is 8184127512.

It is not an unprimeable number, because it can be changed into a prime (2157214819) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 204268 + ... + 214568.

It is an arithmetic number, because the mean of its divisors is an integer number (77883120).

Almost surely, 2^2157214818 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 2157214818, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2492259840).

2157214818 is an abundant number, since it is smaller than the sum of its proper divisors (2827304862).

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

2157214818 is a wasteful number, since it uses less digits than its factorization.

2157214818 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10503.

The product of its digits is 35840, while the sum is 39.

The square root of 2157214818 is about 46445.8267016532. The cubic root of 2157214818 is about 1292.1049738662.

The spelling of 2157214818 in words is "two billion, one hundred fifty-seven million, two hundred fourteen thousand, eight hundred eighteen".