20907666 has 96 divisors (see below), whose sum is σ = 52704000. Its totient is φ = 6132672.

The previous prime is 20907659. The next prime is 20907673. The reversal of 20907666 is 66670902.

It is an interprime number because it is at equal distance from previous prime (20907659) and next prime (20907673).

It is a hoax number, since the sum of its digits (36) coincides with the sum of the digits of its distinct prime factors.

It is a self number, because there is not a number n which added to its sum of digits gives 20907666.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 264615 + ... + 264693.

It is an arithmetic number, because the mean of its divisors is an integer number (549000).

Almost surely, 2^20907666 is an apocalyptic number.

20907666 is a gapful number since it is divisible by the number (26) formed by its first and last digit.

It is a practical number, because each smaller number is the sum of distinct divisors of 20907666, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (26352000).

20907666 is an abundant number, since it is smaller than the sum of its proper divisors (31796334).

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

20907666 is a wasteful number, since it uses less digits than its factorization.

20907666 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 145 (or 126 counting only the distinct ones).

The product of its (nonzero) digits is 27216, while the sum is 36.

The square root of 20907666 is about 4572.4901312086. The cubic root of 20907666 is about 275.4874703761.

The spelling of 20907666 in words is "twenty million, nine hundred seven thousand, six hundred sixty-six".