87915779905 has 8 divisors (see below), whose sum is σ = 111704755752. Its totient is φ = 66195410688.

The previous prime is 87915779881. The next prime is 87915779911. The reversal of 87915779905 is 50997751978.

It can be written as a sum of positive squares in 4 ways, for example, as 21191207184 + 66724572721 = 145572^2 + 258311^2 .

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

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-87915779905 is a prime.

It is a Duffinian number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 517151562 + ... + 517151731.

It is an arithmetic number, because the mean of its divisors is an integer number (13963094469).

Almost surely, 2^87915779905 is an apocalyptic number.

87915779905 is a gapful number since it is divisible by the number (85) formed by its first and last digit.

It is an amenable number.

87915779905 is a deficient number, since it is larger than the sum of its proper divisors (23788975847).

87915779905 is a wasteful number, since it uses less digits than its factorization.

87915779905 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1034303315.

The product of its (nonzero) digits is 50009400, while the sum is 67.

The spelling of 87915779905 in words is "eighty-seven billion, nine hundred fifteen million, seven hundred seventy-nine thousand, nine hundred five".