21853011 has 8 divisors (see below), whose sum is σ = 29163520. Its totient is φ = 14555592.

The previous prime is 21853009. The next prime is 21853031. The reversal of 21853011 is 11035812.

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

It is not a de Polignac number, because 21853011 - 2¹ = 21853009 is a prime.

It is a super-2 number, since 2×21853011² = 955108179532242, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21853001) 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, 1710 + ... + 6828.

It is an arithmetic number, because the mean of its divisors is an integer number (3645440).

Almost surely, 2^21853011 is an apocalyptic number.

21853011 is a deficient number, since it is larger than the sum of its proper divisors (7310509).

21853011 is a wasteful number, since it uses less digits than its factorization.

21853011 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6545.

The product of its (nonzero) digits is 240, while the sum is 21.

The square root of 21853011 is about 4674.7204194476. The cubic root of 21853011 is about 279.5784941942.

Adding to 21853011 its reverse (11035812), we get a palindrome (32888823).

The spelling of 21853011 in words is "twenty-one million, eight hundred fifty-three thousand, eleven".