1661923 has 8 divisors (see below), whose sum is σ = 1707200. Its totient is φ = 1617408.

The previous prime is 1661917. The next prime is 1661939. The reversal of 1661923 is 3291661.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 1661923 - 2¹³ = 1653731 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 1661891 and 1661900.

It is not an unprimeable number, because it can be changed into a prime (1661953) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 8515 + ... + 8707.

It is an arithmetic number, because the mean of its divisors is an integer number (213400).

2^1661923 is an apocalyptic number.

1661923 is a deficient number, since it is larger than the sum of its proper divisors (45277).

1661923 is a wasteful number, since it uses less digits than its factorization.

1661923 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 381.

The product of its digits is 1944, while the sum is 28.

The square root of 1661923 is about 1289.1559254024. The cubic root of 1661923 is about 118.4505184878.

The spelling of 1661923 in words is "one million, six hundred sixty-one thousand, nine hundred twenty-three".