2157923 has 2 divisors, whose sum is σ = 2157924. Its totient is φ = 2157922.

The previous prime is 2157913. The next prime is 2157989. The reversal of 2157923 is 3297512.

2157923 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 2157923 - 2⁴ = 2157907 is a prime.

It is a Sophie Germain prime.

It is not a weakly prime, because it can be changed into another prime (2157913) 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 as a sum of consecutive naturals, namely, 1078961 + 1078962.

It is an arithmetic number, because the mean of its divisors is an integer number (1078962).

2^2157923 is an apocalyptic number.

2157923 is a deficient number, since it is larger than the sum of its proper divisors (1).

2157923 is an equidigital number, since it uses as much as digits as its factorization.

2157923 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 3780, while the sum is 29.

The square root of 2157923 is about 1468.9870659744. The cubic root of 2157923 is about 129.2246351437.

The spelling of 2157923 in words is "two million, one hundred fifty-seven thousand, nine hundred twenty-three".