20417893618 has 4 divisors (see below), whose sum is σ = 30626840430. Its totient is φ = 10208946808.

The previous prime is 20417893609. The next prime is 20417893633. The reversal of 20417893618 is 81639871402.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in only one way, i.e., 17711084889 + 2706808729 = 133083^2 + 52027^2 .

It is a Smith number, since the sum of its digits (49) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 5104473403 + ... + 5104473406.

Almost surely, 2^20417893618 is an apocalyptic number.

20417893618 is a deficient number, since it is larger than the sum of its proper divisors (10208946812).

20417893618 is a wasteful number, since it uses less digits than its factorization.

20417893618 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10208946811.

The product of its (nonzero) digits is 580608, while the sum is 49.

The spelling of 20417893618 in words is "twenty billion, four hundred seventeen million, eight hundred ninety-three thousand, six hundred eighteen".