61997687 has 2 divisors, whose sum is σ = 61997688. Its totient is φ = 61997686.

The previous prime is 61997641. The next prime is 61997707. The reversal of 61997687 is 78679916.

It is a happy number.

61997687 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 61997687 - 2²⁴ = 45220471 is a prime.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (61997587) 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 as a sum of consecutive naturals, namely, 30998843 + 30998844.

It is an arithmetic number, because the mean of its divisors is an integer number (30998844).

Almost surely, 2^61997687 is an apocalyptic number.

61997687 is a deficient number, since it is larger than the sum of its proper divisors (1).

61997687 is an equidigital number, since it uses as much as digits as its factorization.

61997687 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 1143072, while the sum is 53.

The square root of 61997687 is about 7873.8609969951. The cubic root of 61997687 is about 395.7842390771.

The spelling of 61997687 in words is "sixty-one million, nine hundred ninety-seven thousand, six hundred eighty-seven".