16634538637 has 4 divisors (see below), whose sum is σ = 16645251420. Its totient is φ = 16623825856.

The previous prime is 16634538629. The next prime is 16634538643. The reversal of 16634538637 is 73683543661.

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

It can be written as a sum of positive squares in 2 ways, for example, as 3098146921 + 13536391716 = 55661^2 + 116346^2 .

It is a cyclic number.

It is not a de Polignac number, because 16634538637 - 2³ = 16634538629 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (16634538677) 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, 5354062 + ... + 5357167.

It is an arithmetic number, because the mean of its divisors is an integer number (4161312855).

Almost surely, 2^16634538637 is an apocalyptic number.

It is an amenable number.

16634538637 is a deficient number, since it is larger than the sum of its proper divisors (10712783).

16634538637 is a wasteful number, since it uses less digits than its factorization.

16634538637 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10712782.

The product of its digits is 6531840, while the sum is 52.

The spelling of 16634538637 in words is "sixteen billion, six hundred thirty-four million, five hundred thirty-eight thousand, six hundred thirty-seven".