1381928 has 8 divisors (see below), whose sum is σ = 2591130. Its totient is φ = 690960.

The previous prime is 1381921. The next prime is 1381967. The reversal of 1381928 is 8291831.

It can be written as a sum of positive squares in only one way, i.e., 1350244 + 31684 = 1162^2 + 178^2 .

It is a tau number, because it is divible by the number of its divisors (8).

It is a plaindrome in base 12.

It is a junction number, because it is equal to n+sod(n) for n = 1381894 and 1381903.

It is not an unprimeable number, because it can be changed into a prime (1381921) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 86363 + ... + 86378.

2^1381928 is an apocalyptic number.

It is an amenable number.

1381928 is a deficient number, since it is larger than the sum of its proper divisors (1209202).

1381928 is a wasteful number, since it uses less digits than its factorization.

1381928 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 172747 (or 172743 counting only the distinct ones).

The product of its digits is 3456, while the sum is 32.

The square root of 1381928 is about 1175.5543373235. The cubic root of 1381928 is about 111.3854521495.

Subtracting 1381928 from its reverse (8291831), we obtain a triangular number (6909903 = T₃₇₁₇).

The spelling of 1381928 in words is "one million, three hundred eighty-one thousand, nine hundred twenty-eight".