53915681 has 4 divisors (see below), whose sum is σ = 54933012. Its totient is φ = 52898352.

The previous prime is 53915639. The next prime is 53915689. The reversal of 53915681 is 18651935.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 18651935 = 5 ⋅3730387.

It can be written as a sum of positive squares in 2 ways, for example, as 43771456 + 10144225 = 6616^2 + 3185^2 .

It is a cyclic number.

It is not a de Polignac number, because 53915681 - 2¹⁰ = 53914657 is a prime.

It is a super-2 number, since 2×53915681² = 5813801315387522, which contains 22 as substring.

It is a Duffinian number.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (53915689) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 508586 + ... + 508691.

It is an arithmetic number, because the mean of its divisors is an integer number (13733253).

Almost surely, 2^53915681 is an apocalyptic number.

It is an amenable number.

53915681 is a deficient number, since it is larger than the sum of its proper divisors (1017331).

53915681 is a wasteful number, since it uses less digits than its factorization.

53915681 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1017330.

The product of its digits is 32400, while the sum is 38.

The square root of 53915681 is about 7342.7298057330. The cubic root of 53915681 is about 377.7794804774.

The spelling of 53915681 in words is "fifty-three million, nine hundred fifteen thousand, six hundred eighty-one".