20671530 has 64 divisors (see below), whose sum is σ = 55617408. Its totient is φ = 4872960.

The previous prime is 20671529. The next prime is 20671531. The reversal of 20671530 is 3517602.

It is an interprime number because it is at equal distance from previous prime (20671529) and next prime (20671531).

It is a self number, because there is not a number n which added to its sum of digits gives 20671530.

It is not an unprimeable number, because it can be changed into a prime (20671531) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 11364 + ... + 13056.

It is an arithmetic number, because the mean of its divisors is an integer number (869022).

Almost surely, 2^20671530 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 20671530, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (27808704).

20671530 is an abundant number, since it is smaller than the sum of its proper divisors (34945878).

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

20671530 is a wasteful number, since it uses less digits than its factorization.

20671530 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1751.

The product of its (nonzero) digits is 1260, while the sum is 24.

The square root of 20671530 is about 4546.5954295495. The cubic root of 20671530 is about 274.4464014581.

The spelling of 20671530 in words is "twenty million, six hundred seventy-one thousand, five hundred thirty".