1538891 has 4 divisors (see below), whose sum is σ = 1629432. Its totient is φ = 1448352.

The previous prime is 1538879. The next prime is 1538893. The reversal of 1538891 is 1988351.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 1988351 = 79 ⋅25169.

It is a cyclic number.

It is not a de Polignac number, because 1538891 - 2¹⁰ = 1537867 is a prime.

It is an Ulam number.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1538893) 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, 45245 + ... + 45278.

It is an arithmetic number, because the mean of its divisors is an integer number (407358).

2^1538891 is an apocalyptic number.

1538891 is a deficient number, since it is larger than the sum of its proper divisors (90541).

1538891 is an equidigital number, since it uses as much as digits as its factorization.

1538891 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 90540.

The product of its digits is 8640, while the sum is 35.

The square root of 1538891 is about 1240.5204552929. The cubic root of 1538891 is about 115.4523081649.

The spelling of 1538891 in words is "one million, five hundred thirty-eight thousand, eight hundred ninety-one".