18439724650 has 12 divisors (see below), whose sum is σ = 34297887942. Its totient is φ = 7375889840.

The previous prime is 18439724647. The next prime is 18439724707. The reversal of 18439724650 is 5642793481.

It is a happy number.

It can be written as a sum of positive squares in 3 ways, for example, as 17315664921 + 1124059729 = 131589^2 + 33527^2 .

It is a junction number, because it is equal to n+sod(n) for n = 18439724594 and 18439724603.

It is an unprimeable number.

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 5 ways as a sum of consecutive naturals, for example, 184397197 + ... + 184397296.

It is a 1-persistent number, because it is pandigital, but 2⋅18439724650 = 36879449300 is not.

Almost surely, 2^18439724650 is an apocalyptic number.

18439724650 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

18439724650 is a deficient number, since it is larger than the sum of its proper divisors (15858163292).

18439724650 is a wasteful number, since it uses less digits than its factorization.

18439724650 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 368794505 (or 368794500 counting only the distinct ones).

The product of its (nonzero) digits is 1451520, while the sum is 49.

The spelling of 18439724650 in words is "eighteen billion, four hundred thirty-nine million, seven hundred twenty-four thousand, six hundred fifty".