61304209 has 2 divisors, whose sum is σ = 61304210. Its totient is φ = 61304208.

The previous prime is 61304183. The next prime is 61304213. The reversal of 61304209 is 90240316.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 48344209 + 12960000 = 6953^2 + 3600^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-61304209 is a prime.

It is a super-2 number, since 2×61304209² = 7516412082231362, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (61304219) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 30652104 + 30652105.

It is an arithmetic number, because the mean of its divisors is an integer number (30652105).

Almost surely, 2^61304209 is an apocalyptic number.

It is an amenable number.

61304209 is a deficient number, since it is larger than the sum of its proper divisors (1).

61304209 is an equidigital number, since it uses as much as digits as its factorization.

61304209 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 1296, while the sum is 25.

The square root of 61304209 is about 7829.7004412685. The cubic root of 61304209 is about 394.3030148576.

The spelling of 61304209 in words is "sixty-one million, three hundred four thousand, two hundred nine".