10256781 has 16 divisors (see below), whose sum is σ = 14348160. Its totient is φ = 6517280.

The previous prime is 10256777. The next prime is 10256783. The reversal of 10256781 is 18765201.

It is not a de Polignac number, because 10256781 - 2² = 10256777 is a prime.

It is a super-2 number, since 2×10256781² = 210403112963922, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (10256783) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 36361 + ... + 36641.

It is an arithmetic number, because the mean of its divisors is an integer number (896760).

Almost surely, 2^10256781 is an apocalyptic number.

It is an amenable number.

10256781 is a deficient number, since it is larger than the sum of its proper divisors (4091379).

10256781 is an frugal number, since it uses more digits than its factorization.

10256781 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 353 (or 307 counting only the distinct ones).

The product of its (nonzero) digits is 3360, while the sum is 30.

The square root of 10256781 is about 3202.6209579031. The cubic root of 10256781 is about 217.2719660524.

The spelling of 10256781 in words is "ten million, two hundred fifty-six thousand, seven hundred eighty-one".