2123437649 has 4 divisors (see below), whose sum is σ = 2248345764. Its totient is φ = 1998529536.

The previous prime is 2123437643. The next prime is 2123437697. The reversal of 2123437649 is 9467343212.

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 1708582225 + 414855424 = 41335^2 + 20368^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-2123437649 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (2123437643) 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, 62454032 + ... + 62454065.

It is an arithmetic number, because the mean of its divisors is an integer number (562086441).

Almost surely, 2^2123437649 is an apocalyptic number.

It is an amenable number.

2123437649 is a deficient number, since it is larger than the sum of its proper divisors (124908115).

2123437649 is a wasteful number, since it uses less digits than its factorization.

2123437649 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 124908114.

The product of its digits is 217728, while the sum is 41.

The square root of 2123437649 is about 46080.7730946433. The cubic root of 2123437649 is about 1285.3256400906.

The spelling of 2123437649 in words is "two billion, one hundred twenty-three million, four hundred thirty-seven thousand, six hundred forty-nine".