61305543021 has 16 divisors (see below), whose sum is σ = 86616869184. Its totient is φ = 38436059904.

The previous prime is 61305543017. The next prime is 61305543023. The reversal of 61305543021 is 12034550316.

It is not a de Polignac number, because 61305543021 - 2² = 61305543017 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 61305543021.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (61305543023) 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 15 ways as a sum of consecutive naturals, for example, 405535 + ... + 535788.

It is an arithmetic number, because the mean of its divisors is an integer number (5413554324).

Almost surely, 2^61305543021 is an apocalyptic number.

It is an amenable number.

61305543021 is a deficient number, since it is larger than the sum of its proper divisors (25311326163).

61305543021 is a wasteful number, since it uses less digits than its factorization.

61305543021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 942620.

The product of its (nonzero) digits is 10800, while the sum is 30.

The spelling of 61305543021 in words is "sixty-one billion, three hundred five million, five hundred forty-three thousand, twenty-one".