61721543284 has 12 divisors (see below), whose sum is σ = 108015393024. Its totient is φ = 30860002424.

The previous prime is 61721543267. The next prime is 61721543311. The reversal of 61721543284 is 48234512716.

It is a self number, because there is not a number n which added to its sum of digits gives 61721543284.

It is a congruent number.

It is an unprimeable number.

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 3 ways as a sum of consecutive naturals, for example, 12459 + ... + 351565.

It is an arithmetic number, because the mean of its divisors is an integer number (9001282752).

Almost surely, 2^61721543284 is an apocalyptic number.

It is an amenable number.

61721543284 is a deficient number, since it is larger than the sum of its proper divisors (46293849740).

61721543284 is a wasteful number, since it uses less digits than its factorization.

61721543284 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 384614 (or 384612 counting only the distinct ones).

The product of its digits is 322560, while the sum is 43.

The spelling of 61721543284 in words is "sixty-one billion, seven hundred twenty-one million, five hundred forty-three thousand, two hundred eighty-four".