16540621 has 8 divisors (see below), whose sum is σ = 17464320. Its totient is φ = 15622272.

The previous prime is 16540619. The next prime is 16540627. The reversal of 16540621 is 12604561.

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 16540621 - 2¹ = 16540619 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (16540627) 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, 6141 + ... + 8413.

It is an arithmetic number, because the mean of its divisors is an integer number (2183040).

Almost surely, 2^16540621 is an apocalyptic number.

It is an amenable number.

16540621 is a deficient number, since it is larger than the sum of its proper divisors (923699).

16540621 is a wasteful number, since it uses less digits than its factorization.

16540621 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2675.

The product of its (nonzero) digits is 1440, while the sum is 25.

The square root of 16540621 is about 4067.0162281456. The cubic root of 16540621 is about 254.7909140879.

It can be divided in two parts, 16540 and 621, that added together give a square (17161 = 131²).

The spelling of 16540621 in words is "sixteen million, five hundred forty thousand, six hundred twenty-one".