1955561985 has 48 divisors (see below), whose sum is σ = 3842529600. Its totient is φ = 912062592.

The previous prime is 1955561981. The next prime is 1955562043. The reversal of 1955561985 is 5891655591.

1955561985 is a `hidden beast` number, since 1 + 9 + 5 + 556 + 1 + 9 + 85 = 666.

It is not a de Polignac number, because 1955561985 - 2² = 1955561981 is a prime.

It is not an unprimeable number, because it can be changed into a prime (1955561981) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 76855 + ... + 99084.

It is an arithmetic number, because the mean of its divisors is an integer number (80052700).

Almost surely, 2^1955561985 is an apocalyptic number.

1955561985 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

It is an amenable number.

1955561985 is a deficient number, since it is larger than the sum of its proper divisors (1886967615).

1955561985 is a wasteful number, since it uses less digits than its factorization.

1955561985 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 175982 (or 175979 counting only the distinct ones).

The product of its digits is 2430000, while the sum is 54.

The square root of 1955561985 is about 44221.7365669871. The cubic root of 1955561985 is about 1250.5196740545.

The spelling of 1955561985 in words is "one billion, nine hundred fifty-five million, five hundred sixty-one thousand, nine hundred eighty-five".