2137556809 has 4 divisors (see below), whose sum is σ = 2137649616. Its totient is φ = 2137464004.

The previous prime is 2137556779. The next prime is 2137556821. The reversal of 2137556809 is 9086557312.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also a brilliant number, because the two primes have the same length.

It is a cyclic number.

It is not a de Polignac number, because 2137556809 - 2⁵ = 2137556777 is a prime.

It is a super-2 number, since 2×2137556809² = 9138298223404524962, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (2137556899) 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, 17262 + ... + 67624.

It is an arithmetic number, because the mean of its divisors is an integer number (534412404).

Almost surely, 2^2137556809 is an apocalyptic number.

It is an amenable number.

2137556809 is a deficient number, since it is larger than the sum of its proper divisors (92807).

2137556809 is an equidigital number, since it uses as much as digits as its factorization.

2137556809 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 92806.

The product of its (nonzero) digits is 453600, while the sum is 46.

The square root of 2137556809 is about 46233.7193939661. The cubic root of 2137556809 is about 1288.1681446651.

The spelling of 2137556809 in words is "two billion, one hundred thirty-seven million, five hundred fifty-six thousand, eight hundred nine".