12121651 has 4 divisors (see below), whose sum is σ = 12512704. Its totient is φ = 11730600.

The previous prime is 12121631. The next prime is 12121661. The reversal of 12121651 is 15612121.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 12121651 - 2⁵ = 12121619 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (12121631) 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, 195480 + ... + 195541.

It is an arithmetic number, because the mean of its divisors is an integer number (3128176).

Almost surely, 2^12121651 is an apocalyptic number.

12121651 is a deficient number, since it is larger than the sum of its proper divisors (391053).

12121651 is an equidigital number, since it uses as much as digits as its factorization.

12121651 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 391052.

The product of its digits is 120, while the sum is 19.

The square root of 12121651 is about 3481.6161477107. The cubic root of 12121651 is about 229.7138912492.

Adding to 12121651 its reverse (15612121), we get a palindrome (27733772).

The spelling of 12121651 in words is "twelve million, one hundred twenty-one thousand, six hundred fifty-one".