55981887 has 16 divisors (see below), whose sum is σ = 80777088. Its totient is φ = 34282080.

The previous prime is 55981879. The next prime is 55981897. The reversal of 55981887 is 78818955.

It is not a de Polignac number, because 55981887 - 2³ = 55981879 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (55981837) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 4828 + ... + 11630.

It is an arithmetic number, because the mean of its divisors is an integer number (5048568).

Almost surely, 2^55981887 is an apocalyptic number.

55981887 is a deficient number, since it is larger than the sum of its proper divisors (24795201).

55981887 is a wasteful number, since it uses less digits than its factorization.

55981887 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7030.

The product of its digits is 806400, while the sum is 51.

The square root of 55981887 is about 7482.1044499526. The cubic root of 55981887 is about 382.5449833892.

The spelling of 55981887 in words is "fifty-five million, nine hundred eighty-one thousand, eight hundred eighty-seven".