1285082781 has 8 divisors (see below), whose sum is σ = 1715190720. Its totient is φ = 855848352.

The previous prime is 1285082759. The next prime is 1285082783. The reversal of 1285082781 is 1872805821.

1285082781 is digitally balanced in base 4, because in such base it contains all the possibile digits an equal number of times.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 1285082781 - 2⁷ = 1285082653 is a prime.

It is a super-2 number, since 2×1285082781² = 3302875508045387922, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1285082783) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 214936 + ... + 220833.

It is an arithmetic number, because the mean of its divisors is an integer number (214398840).

Almost surely, 2^1285082781 is an apocalyptic number.

It is an amenable number.

1285082781 is a deficient number, since it is larger than the sum of its proper divisors (430107939).

1285082781 is an equidigital number, since it uses as much as digits as its factorization.

1285082781 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 436755.

The product of its (nonzero) digits is 71680, while the sum is 42.

The square root of 1285082781 is about 35848.0512859486. The cubic root of 1285082781 is about 1087.2023141872.

The spelling of 1285082781 in words is "one billion, two hundred eighty-five million, eighty-two thousand, seven hundred eighty-one".