2031256643 has 4 divisors (see below), whose sum is σ = 2187507168. Its totient is φ = 1875006120.

The previous prime is 2031256639. The next prime is 2031256651. The reversal of 2031256643 is 3466521302.

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

It is not a de Polignac number, because 2031256643 - 2² = 2031256639 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (2031256613) 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, 78125243 + ... + 78125268.

It is an arithmetic number, because the mean of its divisors is an integer number (546876792).

Almost surely, 2^2031256643 is an apocalyptic number.

2031256643 is a deficient number, since it is larger than the sum of its proper divisors (156250525).

2031256643 is a wasteful number, since it uses less digits than its factorization.

2031256643 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 156250524.

The product of its (nonzero) digits is 25920, while the sum is 32.

The square root of 2031256643 is about 45069.4646407077. The cubic root of 2031256643 is about 1266.4506353723.

Adding to 2031256643 its reverse (3466521302), we get a palindrome (5497777945).

The spelling of 2031256643 in words is "two billion, thirty-one million, two hundred fifty-six thousand, six hundred forty-three".