21560945 has 8 divisors (see below), whose sum is σ = 29569344. Its totient is φ = 14784624.

The previous prime is 21560941. The next prime is 21560969. The reversal of 21560945 is 54906512.

It is a happy number.

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 21560945 - 2² = 21560941 is a prime.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (21560941) 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, 307979 + ... + 308048.

It is an arithmetic number, because the mean of its divisors is an integer number (3696168).

Almost surely, 2^21560945 is an apocalyptic number.

It is an amenable number.

21560945 is a deficient number, since it is larger than the sum of its proper divisors (8008399).

21560945 is an equidigital number, since it uses as much as digits as its factorization.

21560945 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 616039.

The product of its (nonzero) digits is 10800, while the sum is 32.

The square root of 21560945 is about 4643.3764654613. The cubic root of 21560945 is about 278.3273794448.

The spelling of 21560945 in words is "twenty-one million, five hundred sixty thousand, nine hundred forty-five".