166621020 has 48 divisors (see below), whose sum is σ = 468357120. Its totient is φ = 44259136.

The previous prime is 166621019. The next prime is 166621031. The reversal of 166621020 is 20126661.

166621020 is digitally balanced in base 3, because in such base it contains all the possibile digits an equal number of times.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 10501 + ... + 21059.

It is an arithmetic number, because the mean of its divisors is an integer number (9757440).

Almost surely, 2^166621020 is an apocalyptic number.

166621020 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

166621020 is an abundant number, since it is smaller than the sum of its proper divisors (301736100).

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

166621020 is a wasteful number, since it uses less digits than its factorization.

166621020 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10834 (or 10832 counting only the distinct ones).

The product of its (nonzero) digits is 864, while the sum is 24.

The square root of 166621020 is about 12908.1764784961. The cubic root of 166621020 is about 550.2709629043.

Adding to 166621020 its reverse (20126661), we get a palindrome (186747681).

The spelling of 166621020 in words is "one hundred sixty-six million, six hundred twenty-one thousand, twenty".