1921523 has 4 divisors (see below), whose sum is σ = 1933920. Its totient is φ = 1909128.

The previous prime is 1921499. The next prime is 1921529. The reversal of 1921523 is 3251291.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 3251291 = 101 ⋅32191.

It is a cyclic number.

It is not a de Polignac number, because 1921523 - 2⁸ = 1921267 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1921529) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 5963 + ... + 6276.

It is an arithmetic number, because the mean of its divisors is an integer number (483480).

2^1921523 is an apocalyptic number.

1921523 is a deficient number, since it is larger than the sum of its proper divisors (12397).

1921523 is a wasteful number, since it uses less digits than its factorization.

1921523 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 12396.

The product of its digits is 540, while the sum is 23.

The square root of 1921523 is about 1386.1901024030. The cubic root of 1921523 is about 124.3221548520.

The spelling of 1921523 in words is "one million, nine hundred twenty-one thousand, five hundred twenty-three".