18945857609 has 16 divisors (see below), whose sum is σ = 21705100032. Its totient is φ = 16199846208.

The previous prime is 18945857603. The next prime is 18945857611. The reversal of 18945857609 is 90675854981.

It is not a de Polignac number, because 18945857609 - 2¹² = 18945853513 is a prime.

It is not an unprimeable number, because it can be changed into a prime (18945857603) 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, 6524852 + ... + 6527754.

It is an arithmetic number, because the mean of its divisors is an integer number (1356568752).

Almost surely, 2^18945857609 is an apocalyptic number.

It is an amenable number.

18945857609 is a deficient number, since it is larger than the sum of its proper divisors (2759242423).

18945857609 is a wasteful number, since it uses less digits than its factorization.

18945857609 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4856.

The product of its (nonzero) digits is 21772800, while the sum is 62.

The spelling of 18945857609 in words is "eighteen billion, nine hundred forty-five million, eight hundred fifty-seven thousand, six hundred nine".