16691488237 has 2 divisors, whose sum is σ = 16691488238. Its totient is φ = 16691488236.

The previous prime is 16691488181. The next prime is 16691488283. The reversal of 16691488237 is 73288419661.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 16254720036 + 436768201 = 127494^2 + 20899^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-16691488237 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (16691788237) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 8345744118 + 8345744119.

It is an arithmetic number, because the mean of its divisors is an integer number (8345744119).

Almost surely, 2^16691488237 is an apocalyptic number.

It is an amenable number.

16691488237 is a deficient number, since it is larger than the sum of its proper divisors (1).

16691488237 is an equidigital number, since it uses as much as digits as its factorization.

16691488237 is an evil number, because the sum of its binary digits is even.

The product of its digits is 3483648, while the sum is 55.

The spelling of 16691488237 in words is "sixteen billion, six hundred ninety-one million, four hundred eighty-eight thousand, two hundred thirty-seven".