18516061651 has 4 divisors (see below), whose sum is σ = 18520023600. Its totient is φ = 18512099704.

The previous prime is 18516061639. The next prime is 18516061661. The reversal of 18516061651 is 15616061581.

It is a happy number.

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 18516061651 - 2¹¹ = 18516059603 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (18516061631) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1973956 + ... + 1983313.

It is an arithmetic number, because the mean of its divisors is an integer number (4630005900).

Almost surely, 2^18516061651 is an apocalyptic number.

18516061651 is a deficient number, since it is larger than the sum of its proper divisors (3961949).

18516061651 is an equidigital number, since it uses as much as digits as its factorization.

18516061651 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3961948.

The product of its (nonzero) digits is 43200, while the sum is 40.

The spelling of 18516061651 in words is "eighteen billion, five hundred sixteen million, sixty-one thousand, six hundred fifty-one".