61607209 has 2 divisors, whose sum is σ = 61607210. Its totient is φ = 61607208.

The previous prime is 61607207. The next prime is 61607233. The reversal of 61607209 is 90270616.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 50013184 + 11594025 = 7072^2 + 3405^2 .

It is a cyclic number.

It is not a de Polignac number, because 61607209 - 2¹ = 61607207 is a prime.

Together with 61607207, it forms a pair of twin primes.

It is a Chen prime.

It is equal to p_3651709 and since 61607209 and 3651709 have the same sum of digits, it is a Honaker prime.

It is not a weakly prime, because it can be changed into another prime (61607207) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 30803604 + 30803605.

It is an arithmetic number, because the mean of its divisors is an integer number (30803605).

Almost surely, 2^61607209 is an apocalyptic number.

It is an amenable number.

61607209 is a deficient number, since it is larger than the sum of its proper divisors (1).

61607209 is an equidigital number, since it uses as much as digits as its factorization.

61607209 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 4536, while the sum is 31.

The square root of 61607209 is about 7849.0259905290. The cubic root of 61607209 is about 394.9515701987.

It can be divided in two parts, 61607 and 209, that added together give a palindrome (61816).

The spelling of 61607209 in words is "sixty-one million, six hundred seven thousand, two hundred nine".