166557203 has 4 divisors (see below), whose sum is σ = 171930048. Its totient is φ = 161184360.

The previous prime is 166557197. The next prime is 166557227. The reversal of 166557203 is 302755661.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 166557203 - 2⁴ = 166557187 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (166557803) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2686376 + ... + 2686437.

It is an arithmetic number, because the mean of its divisors is an integer number (42982512).

Almost surely, 2^166557203 is an apocalyptic number.

166557203 is a deficient number, since it is larger than the sum of its proper divisors (5372845).

166557203 is an equidigital number, since it uses as much as digits as its factorization.

166557203 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5372844.

The product of its (nonzero) digits is 37800, while the sum is 35.

The square root of 166557203 is about 12905.7042814408. The cubic root of 166557203 is about 550.2007014085.

The spelling of 166557203 in words is "one hundred sixty-six million, five hundred fifty-seven thousand, two hundred three".