21052355 has 8 divisors (see below), whose sum is σ = 25456464. Its totient is φ = 16712800.

The previous prime is 21052351. The next prime is 21052373. The reversal of 21052355 is 55325012.

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

It is not a de Polignac number, because 21052355 - 2² = 21052351 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 21052355.

It is not an unprimeable number, because it can be changed into a prime (21052351) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 15416 + ... + 16725.

It is an arithmetic number, because the mean of its divisors is an integer number (3182058).

Almost surely, 2^21052355 is an apocalyptic number.

21052355 is a deficient number, since it is larger than the sum of its proper divisors (4404109).

21052355 is a wasteful number, since it uses less digits than its factorization.

21052355 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 32277.

The product of its (nonzero) digits is 1500, while the sum is 23.

The square root of 21052355 is about 4588.2845378202. The cubic root of 21052355 is about 276.1215027240.

Adding to 21052355 its reverse (55325012), we get a palindrome (76377367).

The spelling of 21052355 in words is "twenty-one million, fifty-two thousand, three hundred fifty-five".