661316155151005 has 8 divisors (see below), whose sum is σ = 793632245752152. Its totient is φ = 529017684406848.

The previous prime is 661316155150997. The next prime is 661316155151011. The reversal of 661316155151005 is 500151551613166.

It can be written as a sum of positive squares in 4 ways, for example, as 56722904794521 + 604593250356484 = 7531461^2 + 24588478^2 .

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

It is a cyclic number.

It is not a de Polignac number, because 661316155151005 - 2³ = 661316155150997 is a prime.

It is a Duffinian number.

It is a congruent 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, 4404881674 + ... + 4405031803.

It is an arithmetic number, because the mean of its divisors is an integer number (99204030719019).

Almost surely, 2^{661316155151005} is an apocalyptic number.

It is an amenable number.

661316155151005 is a deficient number, since it is larger than the sum of its proper divisors (132316090601147).

661316155151005 is a wasteful number, since it uses less digits than its factorization.

661316155151005 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8809928495.

The product of its (nonzero) digits is 405000, while the sum is 46.

The spelling of 661316155151005 in words is "six hundred sixty-one trillion, three hundred sixteen billion, one hundred fifty-five million, one hundred fifty-one thousand, five".