21040144511 has 4 divisors (see below), whose sum is σ = 21293640312. Its totient is φ = 20786648712.

The previous prime is 21040144501. The next prime is 21040144529. The reversal of 21040144511 is 11544104012.

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 21040144511 - 2¹⁴ = 21040128127 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21040144501) 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, 126747776 + ... + 126747941.

It is an arithmetic number, because the mean of its divisors is an integer number (5323410078).

Almost surely, 2^21040144511 is an apocalyptic number.

21040144511 is a deficient number, since it is larger than the sum of its proper divisors (253495801).

21040144511 is an equidigital number, since it uses as much as digits as its factorization.

21040144511 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 253495800.

The product of its (nonzero) digits is 640, while the sum is 23.

Adding to 21040144511 its reverse (11544104012), we get a palindrome (32584248523).

The spelling of 21040144511 in words is "twenty-one billion, forty million, one hundred forty-four thousand, five hundred eleven".