2194643957 has 4 divisors (see below), whose sum is σ = 2394157056. Its totient is φ = 1995130860.

The previous prime is 2194643929. The next prime is 2194644013. The reversal of 2194643957 is 7593464912.

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.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-2194643957 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2194643657) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 99756533 + ... + 99756554.

It is an arithmetic number, because the mean of its divisors is an integer number (598539264).

Almost surely, 2^2194643957 is an apocalyptic number.

It is an amenable number.

2194643957 is a deficient number, since it is larger than the sum of its proper divisors (199513099).

2194643957 is a wasteful number, since it uses less digits than its factorization.

2194643957 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 199513098.

The product of its digits is 1632960, while the sum is 50.

The square root of 2194643957 is about 46847.0271949032. The cubic root of 2194643957 is about 1299.5351310253.

The spelling of 2194643957 in words is "two billion, one hundred ninety-four million, six hundred forty-three thousand, nine hundred fifty-seven".