77991000506 has 8 divisors (see below), whose sum is σ = 120760258944. Its totient is φ = 37737580860.

The previous prime is 77991000491. The next prime is 77991000509. The reversal of 77991000506 is 60500019977.

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

It is not an unprimeable number, because it can be changed into a prime (77991000509) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 628959620 + ... + 628959743.

It is an arithmetic number, because the mean of its divisors is an integer number (15095032368).

Almost surely, 2^77991000506 is an apocalyptic number.

77991000506 is a deficient number, since it is larger than the sum of its proper divisors (42769258438).

77991000506 is a wasteful number, since it uses less digits than its factorization.

77991000506 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1257919396.

The product of its (nonzero) digits is 119070, while the sum is 44.

The spelling of 77991000506 in words is "seventy-seven billion, nine hundred ninety-one million, five hundred six", and thus it is an aban number.