2145706249 has 4 divisors (see below), whose sum is σ = 2145854980. Its totient is φ = 2145557520.

The previous prime is 2145706243. The next prime is 2145706267. The reversal of 2145706249 is 9426075412.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 1381460224 + 764246025 = 37168^2 + 27645^2 .

It is a cyclic number.

It is not a de Polignac number, because 2145706249 - 2¹⁷ = 2145575177 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (2145706243) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 50082 + ... + 82459.

It is an arithmetic number, because the mean of its divisors is an integer number (536463745).

Almost surely, 2^2145706249 is an apocalyptic number.

It is an amenable number.

2145706249 is a deficient number, since it is larger than the sum of its proper divisors (148731).

2145706249 is a wasteful number, since it uses less digits than its factorization.

2145706249 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 148730.

The product of its (nonzero) digits is 120960, while the sum is 40.

The square root of 2145706249 is about 46321.7686298785. The cubic root of 2145706249 is about 1289.8031165985.

The spelling of 2145706249 in words is "two billion, one hundred forty-five million, seven hundred six thousand, two hundred forty-nine".