20857545 has 12 divisors (see below), whose sum is σ = 36153156. Its totient is φ = 11124000.

The previous prime is 20857531. The next prime is 20857553. The reversal of 20857545 is 54575802.

It is a happy number.

It can be written as a sum of positive squares in 2 ways, for example, as 2913849 + 17943696 = 1707^2 + 4236^2 .

It is not a de Polignac number, because 20857545 - 2²¹ = 18760393 is a prime.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 231706 + ... + 231795.

It is an arithmetic number, because the mean of its divisors is an integer number (3012763).

Almost surely, 2^20857545 is an apocalyptic number.

It is an amenable number.

20857545 is a deficient number, since it is larger than the sum of its proper divisors (15295611).

20857545 is a wasteful number, since it uses less digits than its factorization.

20857545 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 463512 (or 463509 counting only the distinct ones).

The product of its (nonzero) digits is 56000, while the sum is 36.

The square root of 20857545 is about 4567.0061309352. The cubic root of 20857545 is about 275.2671563575.

The spelling of 20857545 in words is "twenty million, eight hundred fifty-seven thousand, five hundred forty-five".