1878868221 has 4 divisors (see below), whose sum is σ = 2505157632. Its totient is φ = 1252578812.

The previous prime is 1878868171. The next prime is 1878868223. The reversal of 1878868221 is 1228688781.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 1228688781 = 3 ⋅409562927.

It is a cyclic number.

It is not a de Polignac number, because 1878868221 - 2²¹ = 1876771069 is a prime.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1878868223) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 313144701 + ... + 313144706.

It is an arithmetic number, because the mean of its divisors is an integer number (626289408).

Almost surely, 2^1878868221 is an apocalyptic number.

It is an amenable number.

1878868221 is a deficient number, since it is larger than the sum of its proper divisors (626289411).

1878868221 is an equidigital number, since it uses as much as digits as its factorization.

1878868221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 626289410.

The product of its digits is 688128, while the sum is 51.

The square root of 1878868221 is about 43345.9135444162. The cubic root of 1878868221 is about 1233.9534416491.

The spelling of 1878868221 in words is "one billion, eight hundred seventy-eight million, eight hundred sixty-eight thousand, two hundred twenty-one".