2191723426 has 4 divisors (see below), whose sum is σ = 3287585142. Its totient is φ = 1095861712.

The previous prime is 2191723423. The next prime is 2191723427. The reversal of 2191723426 is 6243271912.

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

It can be written as a sum of positive squares in only one way, i.e., 2121984225 + 69739201 = 46065^2 + 8351^2 .

It is not an unprimeable number, because it can be changed into a prime (2191723421) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 547930855 + ... + 547930858.

Almost surely, 2^2191723426 is an apocalyptic number.

2191723426 is a deficient number, since it is larger than the sum of its proper divisors (1095861716).

2191723426 is a wasteful number, since it uses less digits than its factorization.

2191723426 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1095861715.

The product of its digits is 36288, while the sum is 37.

The square root of 2191723426 is about 46815.8458857682. The cubic root of 2191723426 is about 1298.9584213164.

The spelling of 2191723426 in words is "two billion, one hundred ninety-one million, seven hundred twenty-three thousand, four hundred twenty-six".