166581303128 has 32 divisors (see below), whose sum is σ = 330841810800. Its totient is φ = 78360640512.

The previous prime is 166581303101. The next prime is 166581303137. The reversal of 166581303128 is 821303185661.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 113276 + ... + 588212.

Almost surely, 2^166581303128 is an apocalyptic number.

It is an amenable number.

166581303128 is a deficient number, since it is larger than the sum of its proper divisors (164260507672).

166581303128 is a wasteful number, since it uses less digits than its factorization.

166581303128 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 477539 (or 477535 counting only the distinct ones).

The product of its (nonzero) digits is 207360, while the sum is 44.

Adding to 166581303128 its reverse (821303185661), we get a palindrome (987884488789).

The spelling of 166581303128 in words is "one hundred sixty-six billion, five hundred eighty-one million, three hundred three thousand, one hundred twenty-eight".