21690295 has 8 divisors (see below), whose sum is σ = 28394640. Its totient is φ = 15774720.

The previous prime is 21690293. The next prime is 21690329. The reversal of 21690295 is 59209612.

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

It is not a de Polignac number, because 21690295 - 2¹ = 21690293 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 21690295.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21690293) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 197130 + ... + 197239.

It is an arithmetic number, because the mean of its divisors is an integer number (3549330).

Almost surely, 2^21690295 is an apocalyptic number.

21690295 is a deficient number, since it is larger than the sum of its proper divisors (6704345).

21690295 is a wasteful number, since it uses less digits than its factorization.

21690295 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 394385.

The product of its (nonzero) digits is 9720, while the sum is 34.

The square root of 21690295 is about 4657.2840798045. The cubic root of 21690295 is about 278.8828574315.

The spelling of 21690295 in words is "twenty-one million, six hundred ninety thousand, two hundred ninety-five".