19727389450 has 12 divisors (see below), whose sum is σ = 36692944470. Its totient is φ = 7890955760.

The previous prime is 19727389439. The next prime is 19727389511. The reversal of 19727389450 is 5498372791.

It is a happy number.

It can be written as a sum of positive squares in 3 ways, for example, as 15560816049 + 4166573401 = 124743^2 + 64549^2 .

It is a junction number, because it is equal to n+sod(n) for n = 19727389391 and 19727389400.

It is an unprimeable number.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 197273845 + ... + 197273944.

Almost surely, 2^19727389450 is an apocalyptic number.

19727389450 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

19727389450 is a deficient number, since it is larger than the sum of its proper divisors (16965555020).

19727389450 is a wasteful number, since it uses less digits than its factorization.

19727389450 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 394547801 (or 394547796 counting only the distinct ones).

The product of its (nonzero) digits is 3810240, while the sum is 55.

The spelling of 19727389450 in words is "nineteen billion, seven hundred twenty-seven million, three hundred eighty-nine thousand, four hundred fifty".