21354669541 has 2 divisors, whose sum is σ = 21354669542. Its totient is φ = 21354669540.

The previous prime is 21354669463. The next prime is 21354669551. The reversal of 21354669541 is 14596645312.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 18233100900 + 3121568641 = 135030^2 + 55871^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21354669541 is a prime.

It is a super-2 number, since 2×21354669541² (a number of 21 digits) contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 21354669491 and 21354669500.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21354669551) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10677334770 + 10677334771.

It is an arithmetic number, because the mean of its divisors is an integer number (10677334771).

Almost surely, 2^21354669541 is an apocalyptic number.

It is an amenable number.

21354669541 is a deficient number, since it is larger than the sum of its proper divisors (1).

21354669541 is an equidigital number, since it uses as much as digits as its factorization.

21354669541 is an evil number, because the sum of its binary digits is even.

The product of its digits is 777600, while the sum is 46.

The spelling of 21354669541 in words is "twenty-one billion, three hundred fifty-four million, six hundred sixty-nine thousand, five hundred forty-one".