21016546 has 8 divisors (see below), whose sum is σ = 33184080. Its totient is φ = 9955188.

The previous prime is 21016519. The next prime is 21016547. The reversal of 21016546 is 64561012.

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

It is a self number, because there is not a number n which added to its sum of digits gives 21016546.

It is not an unprimeable number, because it can be changed into a prime (21016547) 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, 276496 + ... + 276571.

It is an arithmetic number, because the mean of its divisors is an integer number (4148010).

Almost surely, 2^21016546 is an apocalyptic number.

21016546 is a deficient number, since it is larger than the sum of its proper divisors (12167534).

21016546 is a wasteful number, since it uses less digits than its factorization.

21016546 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 553088.

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

The square root of 21016546 is about 4584.3806560974. The cubic root of 21016546 is about 275.9648575994.

Adding to 21016546 its reverse (64561012), we get a palindrome (85577558).

The spelling of 21016546 in words is "twenty-one million, sixteen thousand, five hundred forty-six".