1878268921 has 9 divisors (see below), whose sum is σ = 1983197583. Its totient is φ = 1778632560.

The previous prime is 1878268901. The next prime is 1878268967. The reversal of 1878268921 is 1298628781.

It is a happy number.

The square root of 1878268921 is 43339.

It is a perfect power (a square), and thus also a powerful number.

It can be written as a sum of positive squares in only one way, i.e., 1129699321 + 748569600 = 33611^2 + 27360^2 .

It is not a de Polignac number, because 1878268921 - 2²⁷ = 1744051193 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1878268901) by changing a digit.

It is a polite number, since it can be written in 8 ways as a sum of consecutive naturals, for example, 822301 + ... + 824581.

It is an arithmetic number, because the mean of its divisors is an integer number (220355287).

Almost surely, 2^1878268921 is an apocalyptic number.

1878268921 is the 43339-th square number.

1878268921 is the 21670-th centered octagonal number.

It is an amenable number.

1878268921 is a deficient number, since it is larger than the sum of its proper divisors (104928662).

1878268921 is an frugal number, since it uses more digits than its factorization.

1878268921 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4600 (or 2300 counting only the distinct ones).

The product of its digits is 774144, while the sum is 52.

The cubic root of 1878268921 is about 1233.8222302226.

The spelling of 1878268921 in words is "one billion, eight hundred seventy-eight million, two hundred sixty-eight thousand, nine hundred twenty-one".