16505206477 has 2 divisors, whose sum is σ = 16505206478. Its totient is φ = 16505206476.

The previous prime is 16505206411. The next prime is 16505206489. The reversal of 16505206477 is 77460250561.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 16215730281 + 289476196 = 127341^2 + 17014^2 .

It is a cyclic number.

It is not a de Polignac number, because 16505206477 - 2³¹ = 14357722829 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (16505201477) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 8252603238 + 8252603239.

It is an arithmetic number, because the mean of its divisors is an integer number (8252603239).

Almost surely, 2^16505206477 is an apocalyptic number.

It is an amenable number.

16505206477 is a deficient number, since it is larger than the sum of its proper divisors (1).

16505206477 is an equidigital number, since it uses as much as digits as its factorization.

16505206477 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 352800, while the sum is 43.

The spelling of 16505206477 in words is "sixteen billion, five hundred five million, two hundred six thousand, four hundred seventy-seven".