166569481638 has 48 divisors (see below), whose sum is σ = 416241814560. Its totient is φ = 47154659328.

The previous prime is 166569481619. The next prime is 166569481643. The reversal of 166569481638 is 836184965661.

166569481638 is a `hidden beast` number, since 1 + 6 + 6 + 569 + 4 + 8 + 1 + 63 + 8 = 666.

It is a Harshad number since it is a multiple of its sum of digits (63).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 6050395 + ... + 6077862.

It is an arithmetic number, because the mean of its divisors is an integer number (8671704470).

Almost surely, 2^166569481638 is an apocalyptic number.

166569481638 is a gapful number since it is divisible by the number (18) formed by its first and last digit.

166569481638 is an abundant number, since it is smaller than the sum of its proper divisors (249672332922).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

166569481638 is a wasteful number, since it uses less digits than its factorization.

166569481638 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 12128381 (or 12128378 counting only the distinct ones).

The product of its digits is 44789760, while the sum is 63.

The spelling of 166569481638 in words is "one hundred sixty-six billion, five hundred sixty-nine million, four hundred eighty-one thousand, six hundred thirty-eight".