18735556957 has 16 divisors (see below), whose sum is σ = 20492161200. Its totient is φ = 17026071552.

The previous prime is 18735556951. The next prime is 18735556991. The reversal of 18735556957 is 75965553781.

It can be written as a sum of positive squares in 8 ways, for example, as 14443472761 + 4292084196 = 120181^2 + 65514^2 .

It is a cyclic number.

It is not a de Polignac number, because 18735556957 - 2³ = 18735556949 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 18735556895 and 18735556904.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18735556951) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 176083 + ... + 261679.

It is an arithmetic number, because the mean of its divisors is an integer number (1280760075).

Almost surely, 2^18735556957 is an apocalyptic number.

It is an amenable number.

18735556957 is a deficient number, since it is larger than the sum of its proper divisors (1756604243).

18735556957 is a wasteful number, since it uses less digits than its factorization.

18735556957 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 85872.

The product of its digits is 39690000, while the sum is 61.

The spelling of 18735556957 in words is "eighteen billion, seven hundred thirty-five million, five hundred fifty-six thousand, nine hundred fifty-seven".