55473781 has 12 divisors (see below), whose sum is σ = 63081900. Its totient is φ = 48688640.

The previous prime is 55473773. The next prime is 55473793. The reversal of 55473781 is 18737455.

It can be written as a sum of positive squares in 2 ways, for example, as 12780625 + 42693156 = 3575^2 + 6534^2 .

It is not a de Polignac number, because 55473781 - 2³ = 55473773 is a prime.

It is a super-2 number, since 2×55473781² = 6154680756871922, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (55473701) 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, 4396 + ... + 11413.

It is an arithmetic number, because the mean of its divisors is an integer number (5256825).

Almost surely, 2^55473781 is an apocalyptic number.

It is an amenable number.

55473781 is a deficient number, since it is larger than the sum of its proper divisors (7608119).

55473781 is a wasteful number, since it uses less digits than its factorization.

55473781 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 15860 (or 15849 counting only the distinct ones).

The product of its digits is 117600, while the sum is 40.

The square root of 55473781 is about 7448.0723009380. The cubic root of 55473781 is about 381.3841052549.

The spelling of 55473781 in words is "fifty-five million, four hundred seventy-three thousand, seven hundred eighty-one".