61245237521 has 8 divisors (see below), whose sum is σ = 67565103144. Its totient is φ = 55155185280.

The previous prime is 61245237491. The next prime is 61245237533. The reversal of 61245237521 is 12573254216.

It can be written as a sum of positive squares in 4 ways, for example, as 70140625 + 61175096896 = 8375^2 + 247336^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 61245237521 - 2⁶ = 61245237457 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (61245231521) 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 in 7 ways as a sum of consecutive naturals, for example, 57452786 + ... + 57453851.

It is an arithmetic number, because the mean of its divisors is an integer number (8445637893).

Almost surely, 2^61245237521 is an apocalyptic number.

It is an amenable number.

61245237521 is a deficient number, since it is larger than the sum of its proper divisors (6319865623).

61245237521 is a wasteful number, since it uses less digits than its factorization.

61245237521 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 114906691.

The product of its digits is 100800, while the sum is 38.

The spelling of 61245237521 in words is "sixty-one billion, two hundred forty-five million, two hundred thirty-seven thousand, five hundred twenty-one".