7661980305 has 192 divisors, whose sum is σ = 16293888000. Its totient is φ = 3325069440.

The previous prime is 7661980301. The next prime is 7661980349. The reversal of 7661980305 is 5030891667.

It is a happy number.

It is not a de Polignac number, because 7661980305 - 2² = 7661980301 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (45).

It is not an unprimeable number, because it can be changed into a prime (7661980301) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 191 ways as a sum of consecutive naturals, for example, 32058376 + ... + 32058614.

It is an arithmetic number, because the mean of its divisors is an integer number (84864000).

Almost surely, 2^7661980305 is an apocalyptic number.

It is an amenable number.

7661980305 is an abundant number, since it is smaller than the sum of its proper divisors (8631907695).

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

7661980305 is a wasteful number, since it uses less digits than its factorization.

7661980305 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 369 (or 352 counting only the distinct ones).

The product of its (nonzero) digits is 272160, while the sum is 45.

The square root of 7661980305 is about 87532.7384753842. The cubic root of 7661980305 is about 1971.4253819712.

The spelling of 7661980305 in words is "seven billion, six hundred sixty-one million, nine hundred eighty thousand, three hundred five".