21292930 has 8 divisors (see below), whose sum is σ = 38327292. Its totient is φ = 8517168.

The previous prime is 21292919. The next prime is 21292937. The reversal of 21292930 is 3929212.

It can be written as a sum of positive squares in 2 ways, for example, as 21150801 + 142129 = 4599^2 + 377^2 .

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 (21292937) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1064637 + ... + 1064656.

Almost surely, 2^21292930 is an apocalyptic number.

21292930 is a deficient number, since it is larger than the sum of its proper divisors (17034362).

21292930 is a wasteful number, since it uses less digits than its factorization.

21292930 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2129300.

The product of its (nonzero) digits is 1944, while the sum is 28.

The square root of 21292930 is about 4614.4262915340. The cubic root of 21292930 is about 277.1693109235.

It can be divided in two parts, 21292 and 930, that added together give a palindrome (22222).

The spelling of 21292930 in words is "twenty-one million, two hundred ninety-two thousand, nine hundred thirty".