61859777855 has 64 divisors (see below), whose sum is σ = 79881043968. Its totient is φ = 45908311680.

The previous prime is 61859777827. The next prime is 61859777869. The reversal of 61859777855 is 55877795816.

It is not a de Polignac number, because 61859777855 - 2¹⁴ = 61859761471 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 63 ways as a sum of consecutive naturals, for example, 90570344 + ... + 90571026.

It is an arithmetic number, because the mean of its divisors is an integer number (1248141312).

Almost surely, 2^61859777855 is an apocalyptic number.

61859777855 is a deficient number, since it is larger than the sum of its proper divisors (18021266113).

61859777855 is a wasteful number, since it uses less digits than its factorization.

61859777855 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 996.

The product of its digits is 148176000, while the sum is 68.

The spelling of 61859777855 in words is "sixty-one billion, eight hundred fifty-nine million, seven hundred seventy-seven thousand, eight hundred fifty-five".