61298561 has 2 divisors, whose sum is σ = 61298562. Its totient is φ = 61298560.

The previous prime is 61298557. The next prime is 61298569. The reversal of 61298561 is 16589216.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 52998400 + 8300161 = 7280^2 + 2881^2 .

It is a cyclic number.

It is not a de Polignac number, because 61298561 - 2² = 61298557 is a prime.

It is an alternating number because its digits alternate between even and odd.

It is not a weakly prime, because it can be changed into another prime (61298569) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 30649280 + 30649281.

It is an arithmetic number, because the mean of its divisors is an integer number (30649281).

Almost surely, 2^61298561 is an apocalyptic number.

It is an amenable number.

61298561 is a deficient number, since it is larger than the sum of its proper divisors (1).

61298561 is an equidigital number, since it uses as much as digits as its factorization.

61298561 is an evil number, because the sum of its binary digits is even.

The product of its digits is 25920, while the sum is 38.

The square root of 61298561 is about 7829.3397550496. The cubic root of 61298561 is about 394.2909053474.

The spelling of 61298561 in words is "sixty-one million, two hundred ninety-eight thousand, five hundred sixty-one".