20786240 has 56 divisors (see below), whose sum is σ = 52422552. Its totient is φ = 7823360.

The previous prime is 20786219. The next prime is 20786251. The reversal of 20786240 is 4268702.

It can be written as a sum of positive squares in 4 ways, for example, as 8620096 + 12166144 = 2936^2 + 3488^2 .

It is a hoax number, since the sum of its digits (29) coincides with the sum of the digits of its distinct prime factors.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 3530 + ... + 7350.

It is an arithmetic number, because the mean of its divisors is an integer number (936117).

Almost surely, 2^20786240 is an apocalyptic number.

20786240 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 20786240, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (26211276).

20786240 is an abundant number, since it is smaller than the sum of its proper divisors (31636312).

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

20786240 is a wasteful number, since it uses less digits than its factorization.

20786240 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3855 (or 3845 counting only the distinct ones).

The product of its (nonzero) digits is 5376, while the sum is 29.

The square root of 20786240 is about 4559.1929110315. The cubic root of 20786240 is about 274.9531159743.

The spelling of 20786240 in words is "twenty million, seven hundred eighty-six thousand, two hundred forty".