53085781 has 16 divisors (see below), whose sum is σ = 65335680. Its totient is φ = 42094080.

The previous prime is 53085763. The next prime is 53085797. The reversal of 53085781 is 18758035.

53085781 = T₂₂₃₈ + T₂₂₃₉ + ... + T₂₂₅₈.

53085781 = 1233² + 1234² + ... + 1266².

It is not a de Polignac number, because 53085781 - 2⁵ = 53085749 is a prime.

It is a super-2 number, since 2×53085781² = 5636200288759922, which contains 22 as substring.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 53085781.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (53085751) 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 15 ways as a sum of consecutive naturals, for example, 3241 + ... + 10801.

It is an arithmetic number, because the mean of its divisors is an integer number (4083480).

Almost surely, 2^53085781 is an apocalyptic number.

It is an amenable number.

53085781 is a deficient number, since it is larger than the sum of its proper divisors (12249899).

53085781 is a wasteful number, since it uses less digits than its factorization.

53085781 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7644.

The product of its (nonzero) digits is 33600, while the sum is 37.

The square root of 53085781 is about 7285.9989706285. The cubic root of 53085781 is about 375.8311189861.

The spelling of 53085781 in words is "fifty-three million, eighty-five thousand, seven hundred eighty-one".