1640923 has 8 divisors (see below), whose sum is σ = 1734656. Its totient is φ = 1549800.

The previous prime is 1640887. The next prime is 1640927. The reversal of 1640923 is 3290461.

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 2^k-1640923 is a prime.

It is a Duffinian number.

1640923 is a lucky number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1640927) 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 7 ways as a sum of consecutive naturals, for example, 718 + ... + 1948.

It is an arithmetic number, because the mean of its divisors is an integer number (216832).

2^1640923 is an apocalyptic number.

1640923 is a deficient number, since it is larger than the sum of its proper divisors (93733).

1640923 is a wasteful number, since it uses less digits than its factorization.

1640923 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1305.

The product of its (nonzero) digits is 1296, while the sum is 25.

The square root of 1640923 is about 1280.9851677518. The cubic root of 1640923 is about 117.9494900168.

The spelling of 1640923 in words is "one million, six hundred forty thousand, nine hundred twenty-three".