21142270811 has 4 divisors (see below), whose sum is σ = 21170726832. Its totient is φ = 21113814792.

The previous prime is 21142270789. The next prime is 21142270817. The reversal of 21142270811 is 11807224112.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 21142270811 - 2²² = 21138076507 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21142270817) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 14226896 + ... + 14228381.

It is an arithmetic number, because the mean of its divisors is an integer number (5292681708).

Almost surely, 2^21142270811 is an apocalyptic number.

21142270811 is a deficient number, since it is larger than the sum of its proper divisors (28456021).

21142270811 is an equidigital number, since it uses as much as digits as its factorization.

21142270811 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 28456020.

The product of its (nonzero) digits is 1792, while the sum is 29.

Adding to 21142270811 its reverse (11807224112), we get a palindrome (32949494923).

The spelling of 21142270811 in words is "twenty-one billion, one hundred forty-two million, two hundred seventy thousand, eight hundred eleven".