52785781 has 6 divisors (see below), whose sum is σ = 55710582. Its totient is φ = 50007240.

The previous prime is 52785769. The next prime is 52785793. The reversal of 52785781 is 18758725.

It is an interprime number because it is at equal distance from previous prime (52785769) and next prime (52785793).

It can be written as a sum of positive squares in only one way, i.e., 48094225 + 4691556 = 6935^2 + 2166^2 .

It is not a de Polignac number, because 52785781 - 2⁹ = 52785269 is a prime.

It is a super-2 number, since 2×52785781² = 5572677351559922, 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 (52785181) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 72750 + ... + 73471.

It is an arithmetic number, because the mean of its divisors is an integer number (9285097).

Almost surely, 2^52785781 is an apocalyptic number.

It is an amenable number.

52785781 is a deficient number, since it is larger than the sum of its proper divisors (2924801).

52785781 is a wasteful number, since it uses less digits than its factorization.

52785781 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 146259 (or 146240 counting only the distinct ones).

The product of its digits is 156800, while the sum is 43.

The square root of 52785781 is about 7265.3823712176. The cubic root of 52785781 is about 375.1218116867.

The spelling of 52785781 in words is "fifty-two million, seven hundred eighty-five thousand, seven hundred eighty-one".