20726440 has 64 divisors (see below), whose sum is σ = 54028800. Its totient is φ = 7008768.

The previous prime is 20726437. The next prime is 20726441. The reversal of 20726440 is 4462702.

It is not an unprimeable number, because it can be changed into a prime (20726441) 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, 21652 + ... + 22588.

It is an arithmetic number, because the mean of its divisors is an integer number (844200).

Almost surely, 2^20726440 is an apocalyptic number.

20726440 is a gapful number since it is divisible by the number (20) 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 20726440, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (27014400).

20726440 is an abundant number, since it is smaller than the sum of its proper divisors (33302360).

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

20726440 is a wasteful number, since it uses less digits than its factorization.

20726440 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1034 (or 1030 counting only the distinct ones).

The product of its (nonzero) digits is 2688, while the sum is 25.

The square root of 20726440 is about 4552.6300091266. The cubic root of 20726440 is about 274.6891915525.

The spelling of 20726440 in words is "twenty million, seven hundred twenty-six thousand, four hundred forty".