1664707 has 4 divisors (see below), whose sum is σ = 1816056. Its totient is φ = 1513360.

The previous prime is 1664701. The next prime is 1664711. The reversal of 1664707 is 7074661.

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

It is a cyclic number.

It is not a de Polignac number, because 1664707 - 2¹⁵ = 1631939 is a prime.

It is an Ulam number.

It is not an unprimeable number, because it can be changed into a prime (1664701) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 75658 + ... + 75679.

It is an arithmetic number, because the mean of its divisors is an integer number (454014).

2^1664707 is an apocalyptic number.

1664707 is a deficient number, since it is larger than the sum of its proper divisors (151349).

1664707 is a wasteful number, since it uses less digits than its factorization.

1664707 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 151348.

The product of its (nonzero) digits is 7056, while the sum is 31.

The square root of 1664707 is about 1290.2352498672. The cubic root of 1664707 is about 118.5166230901.

The spelling of 1664707 in words is "one million, six hundred sixty-four thousand, seven hundred seven".