67721239780 has 24 divisors (see below), whose sum is σ = 150580169208. Its totient is φ = 25495054848.

The previous prime is 67721239771. The next prime is 67721239787. The reversal of 67721239780 is 8793212776.

It can be written as a sum of positive squares in 4 ways, for example, as 27481682176 + 40239557604 = 165776^2 + 200598^2 .

It is a hoax number, since the sum of its digits (52) coincides with the sum of the digits of its distinct prime factors.

It is not an unprimeable number, because it can be changed into a prime (67721239787) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 99589719 + ... + 99590398.

It is an arithmetic number, because the mean of its divisors is an integer number (6274173717).

Almost surely, 2^67721239780 is an apocalyptic number.

It is an amenable number.

67721239780 is an abundant number, since it is smaller than the sum of its proper divisors (82858929428).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

67721239780 is a wasteful number, since it uses less digits than its factorization.

67721239780 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 199180143 (or 199180141 counting only the distinct ones).

The product of its (nonzero) digits is 1778112, while the sum is 52.

The spelling of 67721239780 in words is "sixty-seven billion, seven hundred twenty-one million, two hundred thirty-nine thousand, seven hundred eighty".