1668541 has 4 divisors (see below), whose sum is σ = 1906912. Its totient is φ = 1430172.

The previous prime is 1668539. The next prime is 1668551. The reversal of 1668541 is 1458661.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 1458661 = 977 ⋅1493.

It is a cyclic number.

It is not a de Polignac number, because 1668541 - 2¹ = 1668539 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1668521) 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, 119175 + ... + 119188.

It is an arithmetic number, because the mean of its divisors is an integer number (476728).

2^1668541 is an apocalyptic number.

It is an amenable number.

1668541 is a deficient number, since it is larger than the sum of its proper divisors (238371).

1668541 is an equidigital number, since it uses as much as digits as its factorization.

1668541 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 238370.

The product of its digits is 5760, while the sum is 31.

The square root of 1668541 is about 1291.7201709349. The cubic root of 1668541 is about 118.6075388569.

It can be divided in two parts, 1668 and 541, that added together give a square (2209 = 47²).

The spelling of 1668541 in words is "one million, six hundred sixty-eight thousand, five hundred forty-one".