61891544653 has 2 divisors, whose sum is σ = 61891544654. Its totient is φ = 61891544652.

The previous prime is 61891544641. The next prime is 61891544731. The reversal of 61891544653 is 35644519816.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 52641336969 + 9250207684 = 229437^2 + 96178^2 .

It is a cyclic number.

It is not a de Polignac number, because 61891544653 - 2²⁵ = 61857990221 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 61891544653.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (61891544633) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 30945772326 + 30945772327.

It is an arithmetic number, because the mean of its divisors is an integer number (30945772327).

Almost surely, 2^61891544653 is an apocalyptic number.

It is an amenable number.

61891544653 is a deficient number, since it is larger than the sum of its proper divisors (1).

61891544653 is an equidigital number, since it uses as much as digits as its factorization.

61891544653 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 3110400, while the sum is 52.

The spelling of 61891544653 in words is "sixty-one billion, eight hundred ninety-one million, five hundred forty-four thousand, six hundred fifty-three".