209481057 has 12 divisors (see below), whose sum is σ = 303121104. Its totient is φ = 139406040.

The previous prime is 209481053. The next prime is 209481059. The reversal of 209481057 is 750184902.

It is not a de Polignac number, because 209481057 - 2² = 209481053 is a prime.

It is a hoax number, since the sum of its digits (36) coincides with the sum of the digits of its distinct prime factors.

It is not an unprimeable number, because it can be changed into a prime (209481053) 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, 15243 + ... + 25520.

It is an arithmetic number, because the mean of its divisors is an integer number (25260092).

Almost surely, 2^209481057 is an apocalyptic number.

It is an amenable number.

209481057 is a deficient number, since it is larger than the sum of its proper divisors (93640047).

209481057 is a wasteful number, since it uses less digits than its factorization.

209481057 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 41340 (or 41337 counting only the distinct ones).

The product of its (nonzero) digits is 20160, while the sum is 36.

The square root of 209481057 is about 14473.4604362606. The cubic root of 209481057 is about 593.9021792458.

The spelling of 209481057 in words is "two hundred nine million, four hundred eighty-one thousand, fifty-seven".