20867040 has 144 divisors (see below), whose sum is σ = 73081008. Its totient is φ = 5419008.

The previous prime is 20867039. The next prime is 20867047. The reversal of 20867040 is 4076802.

It is a tau number, because it is divible by the number of its divisors (144).

It is a junction number, because it is equal to n+sod(n) for n = 20866995 and 20867013.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20867047) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 61752 + ... + 62088.

It is an arithmetic number, because the mean of its divisors is an integer number (507507).

Almost surely, 2^20867040 is an apocalyptic number.

20867040 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 20867040, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (36540504).

20867040 is an abundant number, since it is smaller than the sum of its proper divisors (52213968).

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

20867040 is a wasteful number, since it uses less digits than its factorization.

20867040 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 401 (or 390 counting only the distinct ones).

The product of its (nonzero) digits is 2688, while the sum is 27.

The square root of 20867040 is about 4568.0455339237. The cubic root of 20867040 is about 275.3089200637.

The spelling of 20867040 in words is "twenty million, eight hundred sixty-seven thousand, forty".