166451563 has 4 divisors (see below), whose sum is σ = 167381640. Its totient is φ = 165521488.

The previous prime is 166451531. The next prime is 166451629. The reversal of 166451563 is 365154661.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 365154661 = 4651 ⋅78511.

It is a cyclic number.

It is not a de Polignac number, because 166451563 - 2⁵ = 166451531 is a prime.

It is a super-2 number, since 2×166451563² = 55412245650285938, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (166457563) 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, 464770 + ... + 465127.

It is an arithmetic number, because the mean of its divisors is an integer number (41845410).

Almost surely, 2^166451563 is an apocalyptic number.

166451563 is a deficient number, since it is larger than the sum of its proper divisors (930077).

166451563 is an equidigital number, since it uses as much as digits as its factorization.

166451563 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 930076.

The product of its digits is 64800, while the sum is 37.

The square root of 166451563 is about 12901.6108684148. The cubic root of 166451563 is about 550.0843540040.

The spelling of 166451563 in words is "one hundred sixty-six million, four hundred fifty-one thousand, five hundred sixty-three".