16640121 has 8 divisors (see below), whose sum is σ = 22786624. Its totient is φ = 10793520.

The previous prime is 16640119. The next prime is 16640123. The reversal of 16640121 is 12104661.

It is an interprime number because it is at equal distance from previous prime (16640119) and next prime (16640123).

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

It is not a de Polignac number, because 16640121 - 2¹ = 16640119 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (16640123) 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, 74845 + ... + 75066.

It is an arithmetic number, because the mean of its divisors is an integer number (2848328).

Almost surely, 2^16640121 is an apocalyptic number.

It is an amenable number.

16640121 is a deficient number, since it is larger than the sum of its proper divisors (6146503).

16640121 is a wasteful number, since it uses less digits than its factorization.

16640121 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 149951.

The product of its (nonzero) digits is 288, while the sum is 21.

The square root of 16640121 is about 4079.2304421300. The cubic root of 16640121 is about 255.3007907694.

Adding to 16640121 its reverse (12104661), we get a palindrome (28744782).

It can be divided in two parts, 16640 and 121, that added together give a palindrome (16761).

The spelling of 16640121 in words is "sixteen million, six hundred forty thousand, one hundred twenty-one".