1928382921 has 6 divisors (see below), whose sum is σ = 2785442010. Its totient is φ = 1285588608.

The previous prime is 1928382919. The next prime is 1928382923. The reversal of 1928382921 is 1292838291.

It is a happy number.

It is an interprime number because it is at equal distance from previous prime (1928382919) and next prime (1928382923).

It can be written as a sum of positive squares in only one way, i.e., 1315077696 + 613305225 = 36264^2 + 24765^2 .

It is not a de Polignac number, because 1928382921 - 2¹ = 1928382919 is a prime.

It is not an unprimeable number, because it can be changed into a prime (1928382923) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 107132376 + ... + 107132393.

It is an arithmetic number, because the mean of its divisors is an integer number (464240335).

Almost surely, 2^1928382921 is an apocalyptic number.

It is an amenable number.

1928382921 is a deficient number, since it is larger than the sum of its proper divisors (857059089).

1928382921 is a wasteful number, since it uses less digits than its factorization.

1928382921 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 214264775 (or 214264772 counting only the distinct ones).

The product of its digits is 124416, while the sum is 45.

The square root of 1928382921 is about 43913.3569771203. The cubic root of 1928382921 is about 1244.6992431690.

The spelling of 1928382921 in words is "one billion, nine hundred twenty-eight million, three hundred eighty-two thousand, nine hundred twenty-one".