21371194541 has 2 divisors, whose sum is σ = 21371194542. Its totient is φ = 21371194540.

The previous prime is 21371194529. The next prime is 21371194553. The reversal of 21371194541 is 14549117312.

It is a balanced prime because it is at equal distance from previous prime (21371194529) and next prime (21371194553).

It can be written as a sum of positive squares in only one way, i.e., 21033700900 + 337493641 = 145030^2 + 18371^2 .

It is a cyclic number.

It is not a de Polignac number, because 21371194541 - 2³⁴ = 4191325357 is a prime.

It is a super-2 number, since 2×21371194541² (a number of 21 digits) contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 21371194495 and 21371194504.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21371194571) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10685597270 + 10685597271.

It is an arithmetic number, because the mean of its divisors is an integer number (10685597271).

Almost surely, 2^21371194541 is an apocalyptic number.

It is an amenable number.

21371194541 is a deficient number, since it is larger than the sum of its proper divisors (1).

21371194541 is an equidigital number, since it uses as much as digits as its factorization.

21371194541 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 30240, while the sum is 38.

The spelling of 21371194541 in words is "twenty-one billion, three hundred seventy-one million, one hundred ninety-four thousand, five hundred forty-one".