20853540 has 36 divisors (see below), whose sum is σ = 63256284. Its totient is φ = 5560896.

The previous prime is 20853529. The next prime is 20853541. The reversal of 20853540 is 4535802.

It can be written as a sum of positive squares in 2 ways, for example, as 7193124 + 13660416 = 2682^2 + 3696^2 .

It is a tau number, because it is divible by the number of its divisors (36).

It is not an unprimeable number, because it can be changed into a prime (20853541) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 57747 + ... + 58106.

It is an arithmetic number, because the mean of its divisors is an integer number (1757119).

Almost surely, 2^20853540 is an apocalyptic number.

20853540 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

20853540 is an abundant number, since it is smaller than the sum of its proper divisors (42402744).

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

20853540 is a wasteful number, since it uses less digits than its factorization.

20853540 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 115868 (or 115863 counting only the distinct ones).

The product of its (nonzero) digits is 4800, while the sum is 27.

The square root of 20853540 is about 4566.5676388290. The cubic root of 20853540 is about 275.2495365860.

It can be divided in two parts, 2085 and 3540, that added together give a square (5625 = 75²).

The spelling of 20853540 in words is "twenty million, eight hundred fifty-three thousand, five hundred forty".