21717553141 has 4 divisors (see below), whose sum is σ = 21734221792. Its totient is φ = 21700884492.

The previous prime is 21717553127. The next prime is 21717553157. The reversal of 21717553141 is 14135571712.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 21717553141 - 2¹³ = 21717544949 is a prime.

It is a super-2 number, since 2×21717553141² (a number of 21 digits) contains 22 as substring.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 21717553141.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21717553171) 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, 8332371 + ... + 8334976.

It is an arithmetic number, because the mean of its divisors is an integer number (5433555448).

Almost surely, 2^21717553141 is an apocalyptic number.

It is an amenable number.

21717553141 is a deficient number, since it is larger than the sum of its proper divisors (16668651).

21717553141 is a wasteful number, since it uses less digits than its factorization.

21717553141 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 16668650.

The product of its digits is 29400, while the sum is 37.

The spelling of 21717553141 in words is "twenty-one billion, seven hundred seventeen million, five hundred fifty-three thousand, one hundred forty-one".