61805006505 has 64 divisors (see below), whose sum is σ = 120124477440. Its totient is φ = 29901009600.

The previous prime is 61805006443. The next prime is 61805006561. The reversal of 61805006505 is 50560050816.

It is not a de Polignac number, because 61805006505 - 2⁹ = 61805005993 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 61805006505.

It is an unprimeable number.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 642610 + ... + 732500.

It is an arithmetic number, because the mean of its divisors is an integer number (1876944960).

Almost surely, 2^61805006505 is an apocalyptic number.

It is an amenable number.

61805006505 is a deficient number, since it is larger than the sum of its proper divisors (58319470935).

61805006505 is a wasteful number, since it uses less digits than its factorization.

61805006505 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 90379 (or 90373 counting only the distinct ones).

The product of its (nonzero) digits is 36000, while the sum is 36.

The spelling of 61805006505 in words is "sixty-one billion, eight hundred five million, six thousand, five hundred five".