12172656 has 40 divisors (see below), whose sum is σ = 31577344. Its totient is φ = 4040640.

The previous prime is 12172649. The next prime is 12172661. The reversal of 12172656 is 65627121.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 17271 + ... + 17961.

Almost surely, 2^12172656 is an apocalyptic number.

12172656 is a gapful number since it is divisible by the number (16) formed by its first and last digit.

It is an amenable number.

12172656 is an abundant number, since it is smaller than the sum of its proper divisors (19404688).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

12172656 is a wasteful number, since it uses less digits than its factorization.

12172656 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1069 (or 1063 counting only the distinct ones).

The product of its digits is 5040, while the sum is 30.

The square root of 12172656 is about 3488.9333613585. The cubic root of 12172656 is about 230.0356340504.

Adding to 12172656 its reverse (65627121), we get a palindrome (77799777).

The spelling of 12172656 in words is "twelve million, one hundred seventy-two thousand, six hundred fifty-six".