1538993 has 4 divisors (see below), whose sum is σ = 1629540. Its totient is φ = 1448448.

The previous prime is 1538989. The next prime is 1539011. The reversal of 1538993 is 3998351.

1538993 is nontrivially palindromic in base 9.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 1385329 + 153664 = 1177^2 + 392^2 .

It is a cyclic number.

It is not a de Polignac number, because 1538993 - 2² = 1538989 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1538963) 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, 45248 + ... + 45281.

It is an arithmetic number, because the mean of its divisors is an integer number (407385).

2^1538993 is an apocalyptic number.

It is an amenable number.

1538993 is a deficient number, since it is larger than the sum of its proper divisors (90547).

1538993 is an equidigital number, since it uses as much as digits as its factorization.

1538993 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 90546.

The product of its digits is 29160, while the sum is 38.

The square root of 1538993 is about 1240.5615663884. The cubic root of 1538993 is about 115.4548588925.

It can be divided in two parts, 153 and 8993, that multiplied together give a square (1375929 = 1173²).

The spelling of 1538993 in words is "one million, five hundred thirty-eight thousand, nine hundred ninety-three".