15664121 has 8 divisors (see below), whose sum is σ = 17323104. Its totient is φ = 14044320.

The previous prime is 15664093. The next prime is 15664133. The reversal of 15664121 is 12146651.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 15664121 - 2¹⁸ = 15401977 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (15664141) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 8951 + ... + 10556.

It is an arithmetic number, because the mean of its divisors is an integer number (2165388).

Almost surely, 2^15664121 is an apocalyptic number.

15664121 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

It is an amenable number.

15664121 is a deficient number, since it is larger than the sum of its proper divisors (1658983).

15664121 is a wasteful number, since it uses less digits than its factorization.

15664121 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 19591.

The product of its digits is 1440, while the sum is 26.

The square root of 15664121 is about 3957.7924402374. The cubic root of 15664121 is about 250.2084714436.

The spelling of 15664121 in words is "fifteen million, six hundred sixty-four thousand, one hundred twenty-one".