23121656 has 8 divisors (see below), whose sum is σ = 43353120. Its totient is φ = 11560824.

The previous prime is 23121643. The next prime is 23121661. The reversal of 23121656 is 65612132.

It is a tau number, because it is divible by the number of its divisors (8).

It is a super-2 number, since 2×23121656² = 1069221952364672, which contains 22 as substring.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1445096 + ... + 1445111.

It is an arithmetic number, because the mean of its divisors is an integer number (5419140).

Almost surely, 2^23121656 is an apocalyptic number.

It is an amenable number.

23121656 is a deficient number, since it is larger than the sum of its proper divisors (20231464).

23121656 is a wasteful number, since it uses less digits than its factorization.

23121656 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2890213 (or 2890209 counting only the distinct ones).

The product of its digits is 2160, while the sum is 26.

The square root of 23121656 is about 4808.4983102836. The cubic root of 23121656 is about 284.8872273636.

Adding to 23121656 its reverse (65612132), we get a palindrome (88733788).

The spelling of 23121656 in words is "twenty-three million, one hundred twenty-one thousand, six hundred fifty-six".