165537663405 has 16 divisors (see below), whose sum is σ = 265802831424. Its totient is φ = 87972563840.

The previous prime is 165537663397. The next prime is 165537663409. The reversal of 165537663405 is 504366735561.

It is not a de Polignac number, because 165537663405 - 2³ = 165537663397 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (165537663409) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 19632519 + ... + 19640948.

It is an arithmetic number, because the mean of its divisors is an integer number (16612676964).

Almost surely, 2^165537663405 is an apocalyptic number.

165537663405 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

It is an amenable number.

165537663405 is a deficient number, since it is larger than the sum of its proper divisors (100265168019).

165537663405 is a wasteful number, since it uses less digits than its factorization.

165537663405 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 39273756.

The product of its (nonzero) digits is 6804000, while the sum is 51.

The spelling of 165537663405 in words is "one hundred sixty-five billion, five hundred thirty-seven million, six hundred sixty-three thousand, four hundred five".