61561187 has 2 divisors, whose sum is σ = 61561188. Its totient is φ = 61561186.

The previous prime is 61561169. The next prime is 61561193. The reversal of 61561187 is 78116516.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 61561187 - 2¹² = 61557091 is a prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (61561127) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 30780593 + 30780594.

It is an arithmetic number, because the mean of its divisors is an integer number (30780594).

Almost surely, 2^61561187 is an apocalyptic number.

61561187 is a deficient number, since it is larger than the sum of its proper divisors (1).

61561187 is an equidigital number, since it uses as much as digits as its factorization.

61561187 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 10080, while the sum is 35.

The square root of 61561187 is about 7846.0937414742. The cubic root of 61561187 is about 394.8531997352.

The spelling of 61561187 in words is "sixty-one million, five hundred sixty-one thousand, one hundred eighty-seven".