2142644809 has 4 divisors (see below), whose sum is σ = 2143130004. Its totient is φ = 2142159616.

The previous prime is 2142644773. The next prime is 2142644821. The reversal of 2142644809 is 9084462412.

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 1361610000 + 781034809 = 36900^2 + 27947^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-2142644809 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (2142644869) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 235912 + ... + 244825.

It is an arithmetic number, because the mean of its divisors is an integer number (535782501).

Almost surely, 2^2142644809 is an apocalyptic number.

It is an amenable number.

2142644809 is a deficient number, since it is larger than the sum of its proper divisors (485195).

2142644809 is an equidigital number, since it uses as much as digits as its factorization.

2142644809 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 485194.

The product of its (nonzero) digits is 110592, while the sum is 40.

The square root of 2142644809 is about 46288.7114640276. The cubic root of 2142644809 is about 1289.1894050226.

The spelling of 2142644809 in words is "two billion, one hundred forty-two million, six hundred forty-four thousand, eight hundred nine".