20801240 has 16 divisors (see below), whose sum is σ = 46802880. Its totient is φ = 8320480.

The previous prime is 20801191. The next prime is 20801243. The reversal of 20801240 is 4210802.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20801243) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 259976 + ... + 260055.

It is an arithmetic number, because the mean of its divisors is an integer number (2925180).

Almost surely, 2^20801240 is an apocalyptic number.

20801240 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

20801240 is an abundant number, since it is smaller than the sum of its proper divisors (26001640).

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

20801240 is a wasteful number, since it uses less digits than its factorization.

20801240 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 520042 (or 520038 counting only the distinct ones).

The product of its (nonzero) digits is 128, while the sum is 17.

The square root of 20801240 is about 4560.8376423635. The cubic root of 20801240 is about 275.0192383235.

The spelling of 20801240 in words is "twenty million, eight hundred one thousand, two hundred forty".