2145805723 has 16 divisors (see below), whose sum is σ = 2303352576. Its totient is φ = 1994430240.

The previous prime is 2145805699. The next prime is 2145805741. The reversal of 2145805723 is 3275085412.

It is not a de Polignac number, because 2145805723 - 2¹³ = 2145797531 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (2145805423) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 107236 + ... + 125662.

It is an arithmetic number, because the mean of its divisors is an integer number (143959536).

Almost surely, 2^2145805723 is an apocalyptic number.

2145805723 is a gapful number since it is divisible by the number (23) formed by its first and last digit.

2145805723 is a deficient number, since it is larger than the sum of its proper divisors (157546853).

2145805723 is a wasteful number, since it uses less digits than its factorization.

2145805723 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 18594.

The product of its (nonzero) digits is 67200, while the sum is 37.

The square root of 2145805723 is about 46322.8423458665. The cubic root of 2145805723 is about 1289.8230478593.

The spelling of 2145805723 in words is "two billion, one hundred forty-five million, eight hundred five thousand, seven hundred twenty-three".