20969286 has 64 divisors (see below), whose sum is σ = 47416320. Its totient is φ = 6140160.

The previous prime is 20969281. The next prime is 20969303. The reversal of 20969286 is 68296902.

20969286 = 364² + 365² + ... + 480².

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20969281) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 252601 + ... + 252683.

It is an arithmetic number, because the mean of its divisors is an integer number (740880).

Almost surely, 2^20969286 is an apocalyptic number.

20969286 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 20969286, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (23708160).

20969286 is an abundant number, since it is smaller than the sum of its proper divisors (26447034).

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

20969286 is a wasteful number, since it uses less digits than its factorization.

20969286 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 221.

The product of its (nonzero) digits is 93312, while the sum is 42.

The square root of 20969286 is about 4579.2232965864. The cubic root of 20969286 is about 275.7578478884.

The spelling of 20969286 in words is "twenty million, nine hundred sixty-nine thousand, two hundred eighty-six".