61504209 has 12 divisors (see below), whose sum is σ = 95673396. Its totient is φ = 37848672.

The previous prime is 61504207. The next prime is 61504211. The reversal of 61504209 is 90240516.

61504209 is a `hidden beast` number, since 615 + 0 + 42 + 0 + 9 = 666.

It is an interprime number because it is at equal distance from previous prime (61504207) and next prime (61504211).

It can be written as a sum of positive squares in 2 ways, for example, as 3027600 + 58476609 = 1740^2 + 7647^2 .

It is not a de Polignac number, because 61504209 - 2¹ = 61504207 is a prime.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (61504207) 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, 262722 + ... + 262955.

It is an arithmetic number, because the mean of its divisors is an integer number (7972783).

Almost surely, 2^61504209 is an apocalyptic number.

It is an amenable number.

61504209 is a deficient number, since it is larger than the sum of its proper divisors (34169187).

61504209 is a wasteful number, since it uses less digits than its factorization.

61504209 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 525696 (or 525693 counting only the distinct ones).

The product of its (nonzero) digits is 2160, while the sum is 27.

The square root of 61504209 is about 7842.4619221262. The cubic root of 61504209 is about 394.7313432469.

The spelling of 61504209 in words is "sixty-one million, five hundred four thousand, two hundred nine".