21721122141 has 8 divisors (see below), whose sum is σ = 29153294784. Its totient is φ = 14384848800.

The previous prime is 21721122133. The next prime is 21721122179. The reversal of 21721122141 is 14122112712.

It is a happy number.

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

It is not a de Polignac number, because 21721122141 - 2³ = 21721122133 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21721122121) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 23974296 + ... + 23975201.

It is an arithmetic number, because the mean of its divisors is an integer number (3644161848).

Almost surely, 2^21721122141 is an apocalyptic number.

It is an amenable number.

21721122141 is a deficient number, since it is larger than the sum of its proper divisors (7432172643).

21721122141 is a wasteful number, since it uses less digits than its factorization.

21721122141 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 47949651.

The product of its digits is 448, while the sum is 24.

Adding to 21721122141 its reverse (14122112712), we get a palindrome (35843234853).

The spelling of 21721122141 in words is "twenty-one billion, seven hundred twenty-one million, one hundred twenty-two thousand, one hundred forty-one".