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12830981 = 26348787
BaseRepresentation
bin110000111100…
…100100000101
3220010212210112
4300330210011
511241042411
61135002405
7214030052
oct60744405
926125715
1012830981
117274119
124369405
1328732c7
1419c0029
1511d6b8b
hexc3c905

12830981 has 4 divisors (see below), whose sum is σ = 12880032. Its totient is φ = 12781932.

The previous prime is 12830959. The next prime is 12830999. The reversal of 12830981 is 18903821.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2k-12830981 is a prime.

It is a super-2 number, since 2×128309812 = 329268146844722, 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 (12830911) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 24131 + ... + 24656.

It is an arithmetic number, because the mean of its divisors is an integer number (3220008).

Almost surely, 212830981 is an apocalyptic number.

It is an amenable number.

12830981 is a deficient number, since it is larger than the sum of its proper divisors (49051).

12830981 is an equidigital number, since it uses as much as digits as its factorization.

12830981 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 49050.

The product of its (nonzero) digits is 3456, while the sum is 32.

The square root of 12830981 is about 3582.0358736339. The cubic root of 12830981 is about 234.1099940669.

The spelling of 12830981 in words is "twelve million, eight hundred thirty thousand, nine hundred eighty-one".

Divisors: 1 263 48787 12830981