21294730 has 8 divisors (see below), whose sum is σ = 38330532. Its totient is φ = 8517888.

The previous prime is 21294719. The next prime is 21294731. The reversal of 21294730 is 3749212.

It can be written as a sum of positive squares in 2 ways, for example, as 20894041 + 400689 = 4571^2 + 633^2 .

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

It is not an unprimeable number, because it can be changed into a prime (21294731) 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, 1064727 + ... + 1064746.

Almost surely, 2^21294730 is an apocalyptic number.

21294730 is a deficient number, since it is larger than the sum of its proper divisors (17035802).

21294730 is a wasteful number, since it uses less digits than its factorization.

21294730 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2129480.

The product of its (nonzero) digits is 3024, while the sum is 28.

The square root of 21294730 is about 4614.6213279098. The cubic root of 21294730 is about 277.1771208820.

It can be divided in two parts, 2129 and 4730, that added together give a cube (6859 = 19³).

The spelling of 21294730 in words is "twenty-one million, two hundred ninety-four thousand, seven hundred thirty".