20645196 has 96 divisors (see below), whose sum is σ = 57915648. Its totient is φ = 5640960.

The previous prime is 20645161. The next prime is 20645197. The reversal of 20645196 is 69154602.

It is a Harshad number since it is a multiple of its sum of digits (33).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20645197) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 90835 + ... + 91061.

It is an arithmetic number, because the mean of its divisors is an integer number (603288).

Almost surely, 2^20645196 is an apocalyptic number.

20645196 is a gapful number since it is divisible by the number (26) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 20645196, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (28957824).

20645196 is an abundant number, since it is smaller than the sum of its proper divisors (37270452).

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

20645196 is a wasteful number, since it uses less digits than its factorization.

20645196 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 311 (or 309 counting only the distinct ones).

The product of its (nonzero) digits is 12960, while the sum is 33.

The square root of 20645196 is about 4543.6984935182. The cubic root of 20645196 is about 274.3298104637.

Adding to 20645196 its reverse (69154602), we get a palindrome (89799798).

It can be divided in two parts, 2064 and 5196, that added together give a triangular number (7260 = T₁₂₀).

The spelling of 20645196 in words is "twenty million, six hundred forty-five thousand, one hundred ninety-six".