61656139 has 2 divisors, whose sum is σ = 61656140. Its totient is φ = 61656138.

The previous prime is 61656131. The next prime is 61656149. The reversal of 61656139 is 93165616.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 61656139 - 2³ = 61656131 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 61656098 and 61656107.

It is not a weakly prime, because it can be changed into another prime (61656131) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 30828069 + 30828070.

It is an arithmetic number, because the mean of its divisors is an integer number (30828070).

Almost surely, 2^61656139 is an apocalyptic number.

61656139 is a deficient number, since it is larger than the sum of its proper divisors (1).

61656139 is an equidigital number, since it uses as much as digits as its factorization.

61656139 is an evil number, because the sum of its binary digits is even.

The product of its digits is 29160, while the sum is 37.

The square root of 61656139 is about 7852.1423191381. The cubic root of 61656139 is about 395.0561026973.

The spelling of 61656139 in words is "sixty-one million, six hundred fifty-six thousand, one hundred thirty-nine".