166784490 has 24 divisors (see below), whose sum is σ = 433639908. Its totient is φ = 44475840.

The previous prime is 166784479. The next prime is 166784521. The reversal of 166784490 is 94487661.

It can be written as a sum of positive squares in 2 ways, for example, as 165868641 + 915849 = 12879^2 + 957^2 .

It is a super-2 number, since 2×166784490² = 55634132209120200, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (45).

It is a Curzon number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 926491 + ... + 926670.

Almost surely, 2^166784490 is an apocalyptic number.

166784490 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

166784490 is an abundant number, since it is smaller than the sum of its proper divisors (266855418).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

166784490 is a wasteful number, since it uses less digits than its factorization.

166784490 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1853174 (or 1853171 counting only the distinct ones).

The product of its (nonzero) digits is 290304, while the sum is 45.

The square root of 166784490 is about 12914.5069592300. The cubic root of 166784490 is about 550.4508589604.

The spelling of 166784490 in words is "one hundred sixty-six million, seven hundred eighty-four thousand, four hundred ninety".