61645806481 has 8 divisors (see below), whose sum is σ = 70490100800. Its totient is φ = 52810949808.

The previous prime is 61645806463. The next prime is 61645806517. The reversal of 61645806481 is 18460854616.

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

It is a cyclic number.

It is not a de Polignac number, because 61645806481 - 2²⁷ = 61511588753 is a prime.

It is a super-2 number, since 2×61645806481² (a number of 22 digits) contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (61645806581) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 2345406 + ... + 2371543.

It is an arithmetic number, because the mean of its divisors is an integer number (8811262600).

Almost surely, 2^61645806481 is an apocalyptic number.

It is an amenable number.

61645806481 is a deficient number, since it is larger than the sum of its proper divisors (8844294319).

61645806481 is a wasteful number, since it uses less digits than its factorization.

61645806481 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4718823.

The product of its (nonzero) digits is 1105920, while the sum is 49.

The spelling of 61645806481 in words is "sixty-one billion, six hundred forty-five million, eight hundred six thousand, four hundred eighty-one".