21142311 has 8 divisors (see below), whose sum is σ = 28214640. Its totient is φ = 14082432.

The previous prime is 21142291. The next prime is 21142343. The reversal of 21142311 is 11324112.

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

It is not a de Polignac number, because 21142311 - 2¹⁷ = 21011239 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21142351) 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, 2101 + ... + 6833.

It is an arithmetic number, because the mean of its divisors is an integer number (3526830).

Almost surely, 2^21142311 is an apocalyptic number.

21142311 is a deficient number, since it is larger than the sum of its proper divisors (7072329).

21142311 is a wasteful number, since it uses less digits than its factorization.

21142311 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6225.

The product of its digits is 48, while the sum is 15.

The square root of 21142311 is about 4598.0768806100. The cubic root of 21142311 is about 276.5142298277.

Adding to 21142311 its reverse (11324112), we get a palindrome (32466423).

The spelling of 21142311 in words is "twenty-one million, one hundred forty-two thousand, three hundred eleven".