781025085 has 84 divisors (see below), whose sum is σ = 1450537788. Its totient is φ = 403481088.

The previous prime is 781025059. The next prime is 781025111. The reversal of 781025085 is 580520187.

It is an interprime number because it is at equal distance from previous prime (781025059) and next prime (781025111).

It can be written as a sum of positive squares in 2 ways, for example, as 315630756 + 465394329 = 17766^2 + 21573^2 .

It is not a de Polignac number, because 781025085 - 2¹⁰ = 781024061 is a prime.

It is a super-2 number, since 2×781025085² = 1220000366798514450, which contains 22 as substring.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 83 ways as a sum of consecutive naturals, for example, 8051757 + ... + 8051853.

It is an arithmetic number, because the mean of its divisors is an integer number (17268307).

Almost surely, 2^781025085 is an apocalyptic number.

It is an amenable number.

781025085 is a deficient number, since it is larger than the sum of its proper divisors (669512703).

781025085 is an frugal number, since it uses more digits than its factorization.

781025085 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 214 (or 152 counting only the distinct ones).

The product of its (nonzero) digits is 22400, while the sum is 36.

The square root of 781025085 is about 27946.8260272969. The cubic root of 781025085 is about 920.9194828231.

The spelling of 781025085 in words is "seven hundred eighty-one million, twenty-five thousand, eighty-five".