166571893021 has 8 divisors (see below), whose sum is σ = 166875024960. Its totient is φ = 166269034752.

The previous prime is 166571893013. The next prime is 166571893027. The reversal of 166571893021 is 120398175661.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 166571893021 - 2³ = 166571893013 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (166571893027) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1170301 + ... + 1304893.

It is an arithmetic number, because the mean of its divisors is an integer number (20859378120).

Almost surely, 2^166571893021 is an apocalyptic number.

It is an amenable number.

166571893021 is a deficient number, since it is larger than the sum of its proper divisors (303131939).

166571893021 is a wasteful number, since it uses less digits than its factorization.

166571893021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 136835.

The product of its (nonzero) digits is 544320, while the sum is 49.

The spelling of 166571893021 in words is "one hundred sixty-six billion, five hundred seventy-one million, eight hundred ninety-three thousand, twenty-one".