1978923 has 8 divisors (see below), whose sum is σ = 2645136. Its totient is φ = 1316000.

The previous prime is 1978913. The next prime is 1978927. The reversal of 1978923 is 3298791.

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 1978923 - 2⁵ = 1978891 is a prime.

It is a super-2 number, since 2×1978923² = 7832272479858, which contains 22 as substring.

1978923 is a lucky number.

It is not an unprimeable number, because it can be changed into a prime (1978927) 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, 1633 + ... + 2573.

It is an arithmetic number, because the mean of its divisors is an integer number (330642).

2^1978923 is an apocalyptic number.

1978923 is a deficient number, since it is larger than the sum of its proper divisors (666213).

1978923 is an equidigital number, since it uses as much as digits as its factorization.

1978923 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1645.

The product of its digits is 27216, while the sum is 39.

The square root of 1978923 is about 1406.7419806063. The cubic root of 1978923 is about 125.5479518140.

The spelling of 1978923 in words is "one million, nine hundred seventy-eight thousand, nine hundred twenty-three".