19773633457 has 4 divisors (see below), whose sum is σ = 19774492276. Its totient is φ = 19772774640.

The previous prime is 19773633437. The next prime is 19773633493. The reversal of 19773633457 is 75433637791.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 75433637791 = 41357 ⋅1823963.

It can be written as a sum of positive squares in 2 ways, for example, as 11168473761 + 8605159696 = 105681^2 + 92764^2 .

It is a cyclic number.

It is not a de Polignac number, because 19773633457 - 2⁷ = 19773633329 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 19773633398 and 19773633407.

It is not an unprimeable number, because it can be changed into a prime (19773633437) 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, 393894 + ... + 441247.

It is an arithmetic number, because the mean of its divisors is an integer number (4943623069).

Almost surely, 2^19773633457 is an apocalyptic number.

It is an amenable number.

19773633457 is a deficient number, since it is larger than the sum of its proper divisors (858819).

19773633457 is an equidigital number, since it uses as much as digits as its factorization.

19773633457 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 858818.

The product of its digits is 10001880, while the sum is 55.

The spelling of 19773633457 in words is "nineteen billion, seven hundred seventy-three million, six hundred thirty-three thousand, four hundred fifty-seven".