21614545 has 4 divisors (see below), whose sum is σ = 25937460. Its totient is φ = 17291632.

The previous prime is 21614539. The next prime is 21614563. The reversal of 21614545 is 54541612.

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

It can be written as a sum of positive squares in 2 ways, for example, as 14085009 + 7529536 = 3753^2 + 2744^2 .

It is a cyclic number.

It is not a de Polignac number, because 21614545 - 2¹¹ = 21612497 is a prime.

It is an alternating number because its digits alternate between even and odd.

It is a plaindrome in base 11.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2161450 + ... + 2161459.

It is an arithmetic number, because the mean of its divisors is an integer number (6484365).

Almost surely, 2^21614545 is an apocalyptic number.

It is an amenable number.

21614545 is a deficient number, since it is larger than the sum of its proper divisors (4322915).

21614545 is an equidigital number, since it uses as much as digits as its factorization.

21614545 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4322914.

The product of its digits is 4800, while the sum is 28.

The square root of 21614545 is about 4649.1445449674. The cubic root of 21614545 is about 278.5578270182.

The spelling of 21614545 in words is "twenty-one million, six hundred fourteen thousand, five hundred forty-five".