61607681 has 2 divisors, whose sum is σ = 61607682. Its totient is φ = 61607680.

The previous prime is 61607659. The next prime is 61607717. The reversal of 61607681 is 18670616.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 38950081 + 22657600 = 6241^2 + 4760^2 .

It is a cyclic number.

It is not a de Polignac number, because 61607681 - 2⁶ = 61607617 is a prime.

It is a super-2 number, since 2×61607681² = 7591012716395522, which contains 22 as substring.

It is a Sophie Germain prime.

It is a Chen prime.

It is a Curzon number.

It is not a weakly prime, because it can be changed into another prime (63607681) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 30803840 + 30803841.

It is an arithmetic number, because the mean of its divisors is an integer number (30803841).

Almost surely, 2^61607681 is an apocalyptic number.

It is an amenable number.

61607681 is a deficient number, since it is larger than the sum of its proper divisors (1).

61607681 is an equidigital number, since it uses as much as digits as its factorization.

61607681 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 12096, while the sum is 35.

The square root of 61607681 is about 7849.0560578964. The cubic root of 61607681 is about 394.9525788289.

The spelling of 61607681 in words is "sixty-one million, six hundred seven thousand, six hundred eighty-one".