21294530 has 16 divisors (see below), whose sum is σ = 38384064. Its totient is φ = 8505840.

The previous prime is 21294517. The next prime is 21294541. The reversal of 21294530 is 3549212.

It is a Curzon number.

It is a self number, because there is not a number n which added to its sum of digits gives 21294530.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 10715 + ... + 12545.

It is an arithmetic number, because the mean of its divisors is an integer number (2399004).

Almost surely, 2^21294530 is an apocalyptic number.

21294530 is a deficient number, since it is larger than the sum of its proper divisors (17089534).

21294530 is a wasteful number, since it uses less digits than its factorization.

21294530 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3001.

The product of its (nonzero) digits is 2160, while the sum is 26.

The square root of 21294530 is about 4614.5996576084. The cubic root of 21294530 is about 277.1762531306.

The spelling of 21294530 in words is "twenty-one million, two hundred ninety-four thousand, five hundred thirty".