1664741 has 8 divisors (see below), whose sum is σ = 1841784.
Its totient is φ = 1494720.
The previous prime is 1664713. The next prime is 1664771. The reversal of 1664741 is 1474661.
It can be written as a sum of positive squares in 4 ways, for example, as 112225 + 1552516 = 335^2 + 1246^2
It is a sphenic number, since it is the product of 3 distinct primes.
It is a cyclic number.
It is a de Polignac number, because none of the positive numbers 2k-1664741 is a prime.
It is a Duffinian number.
It is a Curzon number.
It is a congruent number.
It is not an unprimeable number, because it can be changed into a prime (1664701) by changing a digit.
It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1250 + ... + 2211.
It is an arithmetic number, because the mean of its divisors is an integer number (230223).
21664741 is an apocalyptic number.
It is an amenable number.
1664741 is a deficient number, since it is larger than the sum of its proper divisors (177043).
1664741 is a wasteful number, since it uses less digits than its factorization.
1664741 is an evil number, because the sum of its binary digits is even.
The sum of its prime factors is 3511.
The product of its digits is 4032, while the sum is 29.
The square root of 1664741 is about 1290.2484256917.
The cubic root of 1664741 is about 118.5174299464.
The spelling of 1664741 in words is "one million, six hundred sixty-four thousand, seven hundred forty-one".