55835721 has 12 divisors (see below), whose sum is σ = 80946372. Its totient is φ = 37087776.

The previous prime is 55835719. The next prime is 55835753. The reversal of 55835721 is 12753855.

55835721 is a `hidden beast` number, since 5 + 5 + 83 + 572 + 1 = 666.

It can be written as a sum of positive squares in 2 ways, for example, as 34574400 + 21261321 = 5880^2 + 4611^2 .

It is not a de Polignac number, because 55835721 - 2¹ = 55835719 is a prime.

It is not an unprimeable number, because it can be changed into a prime (55835711) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 8706 + ... + 13691.

It is an arithmetic number, because the mean of its divisors is an integer number (6745531).

Almost surely, 2^55835721 is an apocalyptic number.

It is an amenable number.

55835721 is a deficient number, since it is larger than the sum of its proper divisors (25110651).

55835721 is a wasteful number, since it uses less digits than its factorization.

55835721 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 22680 (or 22677 counting only the distinct ones).

The product of its digits is 42000, while the sum is 36.

The square root of 55835721 is about 7472.3303593993. The cubic root of 55835721 is about 382.2117577240.

The spelling of 55835721 in words is "fifty-five million, eight hundred thirty-five thousand, seven hundred twenty-one".