209842461 has 8 divisors (see below), whose sum is σ = 310877760. Its totient is φ = 139894956.

The previous prime is 209842453. The next prime is 209842471. The reversal of 209842461 is 164248902.

It is not a de Polignac number, because 209842461 - 2³ = 209842453 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (209842471) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 3885945 + ... + 3885998.

It is an arithmetic number, because the mean of its divisors is an integer number (38859720).

Almost surely, 2^209842461 is an apocalyptic number.

It is an amenable number.

209842461 is a deficient number, since it is larger than the sum of its proper divisors (101035299).

209842461 is an equidigital number, since it uses as much as digits as its factorization.

209842461 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7771952 (or 7771946 counting only the distinct ones).

The product of its (nonzero) digits is 27648, while the sum is 36.

The square root of 209842461 is about 14485.9401144696. The cubic root of 209842461 is about 594.2435232484.

The spelling of 209842461 in words is "two hundred nine million, eight hundred forty-two thousand, four hundred sixty-one".