18521117037 has 6 divisors (see below), whose sum is σ = 26752724622. Its totient is φ = 12347411352.

The previous prime is 18521116931. The next prime is 18521117081. The reversal of 18521117037 is 73071112581.

18521117037 is a `hidden beast` number, since 18 + 521 + 117 + 0 + 3 + 7 = 666.

It can be written as a sum of positive squares in only one way, i.e., 14665452201 + 3855664836 = 121101^2 + 62094^2 .

It is not a de Polignac number, because 18521117037 - 2¹⁰ = 18521116013 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 18521116992 and 18521117010.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18521117137) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 1028950938 + ... + 1028950955.

It is an arithmetic number, because the mean of its divisors is an integer number (4458787437).

Almost surely, 2^18521117037 is an apocalyptic number.

It is an amenable number.

18521117037 is a deficient number, since it is larger than the sum of its proper divisors (8231607585).

18521117037 is a wasteful number, since it uses less digits than its factorization.

18521117037 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2057901899 (or 2057901896 counting only the distinct ones).

The product of its (nonzero) digits is 11760, while the sum is 36.

The spelling of 18521117037 in words is "eighteen billion, five hundred twenty-one million, one hundred seventeen thousand, thirty-seven".