166354142521 has 16 divisors (see below), whose sum is σ = 190906055680. Its totient is φ = 141999953040.

The previous prime is 166354142519. The next prime is 166354142543. The reversal of 166354142521 is 125241453661.

It is a cyclic number.

It is not a de Polignac number, because 166354142521 - 2¹ = 166354142519 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (166354145521) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 2061940 + ... + 2141098.

It is an arithmetic number, because the mean of its divisors is an integer number (11931628480).

Almost surely, 2^166354142521 is an apocalyptic number.

It is an amenable number.

166354142521 is a deficient number, since it is larger than the sum of its proper divisors (24551913159).

166354142521 is an equidigital number, since it uses as much as digits as its factorization.

166354142521 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 80404.

The product of its digits is 172800, while the sum is 40.

The spelling of 166354142521 in words is "one hundred sixty-six billion, three hundred fifty-four million, one hundred forty-two thousand, five hundred twenty-one".