20860440 has 64 divisors (see below), whose sum is σ = 63106560. Its totient is φ = 5516160.

The previous prime is 20860409. The next prime is 20860451. The reversal of 20860440 is 4406802.

It is a Harshad number since it is a multiple of its sum of digits (24).

It is a self number, because there is not a number n which added to its sum of digits gives 20860440.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 15057 + ... + 16383.

It is an arithmetic number, because the mean of its divisors is an integer number (986040).

Almost surely, 2^20860440 is an apocalyptic number.

20860440 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 20860440, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (31553280).

20860440 is an abundant number, since it is smaller than the sum of its proper divisors (42246120).

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

20860440 is a wasteful number, since it uses less digits than its factorization.

20860440 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1472 (or 1468 counting only the distinct ones).

The product of its (nonzero) digits is 1536, while the sum is 24.

The square root of 20860440 is about 4567.3230671806. The cubic root of 20860440 is about 275.2798913422.

The spelling of 20860440 in words is "twenty million, eight hundred sixty thousand, four hundred forty".