20531056 has 80 divisors (see below), whose sum is σ = 49996800. Its totient is φ = 7951104.

The previous prime is 20531023. The next prime is 20531059. The reversal of 20531056 is 65013502.

It is a happy number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20531059) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 85785 + ... + 86023.

It is an arithmetic number, because the mean of its divisors is an integer number (624960).

Almost surely, 2^20531056 is an apocalyptic number.

20531056 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 20531056, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (24998400).

20531056 is an abundant number, since it is smaller than the sum of its proper divisors (29465744).

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

20531056 is a wasteful number, since it uses less digits than its factorization.

20531056 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 326 (or 320 counting only the distinct ones).

The product of its (nonzero) digits is 900, while the sum is 22.

The square root of 20531056 is about 4531.1208326417. The cubic root of 20531056 is about 273.8233183513.

Adding to 20531056 its reverse (65013502), we get a palindrome (85544558).

The spelling of 20531056 in words is "twenty million, five hundred thirty-one thousand, fifty-six".