21560090 has 8 divisors (see below), whose sum is σ = 38808180. Its totient is φ = 8624032.

The previous prime is 21560087. The next prime is 21560107. The reversal of 21560090 is 9006512.

It can be written as a sum of positive squares in 2 ways, for example, as 20151121 + 1408969 = 4489^2 + 1187^2 .

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

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1077995 + ... + 1078014.

Almost surely, 2^21560090 is an apocalyptic number.

21560090 is a deficient number, since it is larger than the sum of its proper divisors (17248090).

21560090 is a wasteful number, since it uses less digits than its factorization.

21560090 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2156016.

The product of its (nonzero) digits is 540, while the sum is 23.

The square root of 21560090 is about 4643.2843979235. The cubic root of 21560090 is about 278.3237003690.

The spelling of 21560090 in words is "twenty-one million, five hundred sixty thousand, ninety".