166620690 has 96 divisors (see below), whose sum is σ = 459950400. Its totient is φ = 41731200.

The previous prime is 166620673. The next prime is 166620697. The reversal of 166620690 is 96026661.

It is a happy number.

It is a super-2 number, since 2×166620690² = 55524908672152200, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (166620697) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 237340 + ... + 238040.

It is an arithmetic number, because the mean of its divisors is an integer number (4791150).

Almost surely, 2^166620690 is an apocalyptic number.

166620690 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is a practical number, because each smaller number is the sum of distinct divisors of 166620690, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (229975200).

166620690 is an abundant number, since it is smaller than the sum of its proper divisors (293329710).

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

166620690 is a wasteful number, since it uses less digits than its factorization.

166620690 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 872 (or 869 counting only the distinct ones).

The product of its (nonzero) digits is 23328, while the sum is 36.

The square root of 166620690 is about 12908.1636958942. The cubic root of 166620690 is about 550.2705996257.

The spelling of 166620690 in words is "one hundred sixty-six million, six hundred twenty thousand, six hundred ninety".