18135865007 has 4 divisors (see below), whose sum is σ = 19530931560. Its totient is φ = 16740798456.

The previous prime is 18135865003. The next prime is 18135865019. The reversal of 18135865007 is 70056853181.

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

It is a cyclic number.

It is not a de Polignac number, because 18135865007 - 2² = 18135865003 is a prime.

It is a super-2 number, since 2×18135865007² (a number of 21 digits) contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18135865001) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 697533257 + ... + 697533282.

It is an arithmetic number, because the mean of its divisors is an integer number (4882732890).

Almost surely, 2^18135865007 is an apocalyptic number.

18135865007 is a deficient number, since it is larger than the sum of its proper divisors (1395066553).

18135865007 is a wasteful number, since it uses less digits than its factorization.

18135865007 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1395066552.

The product of its (nonzero) digits is 201600, while the sum is 44.

The spelling of 18135865007 in words is "eighteen billion, one hundred thirty-five million, eight hundred sixty-five thousand, seven".