21041435531 has 2 divisors, whose sum is σ = 21041435532. Its totient is φ = 21041435530.

The previous prime is 21041435491. The next prime is 21041435567. The reversal of 21041435531 is 13553414012.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 21041435531 - 2¹⁰ = 21041434507 is a prime.

It is a super-2 number, since 2×21041435531² (a number of 21 digits) contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 21041435494 and 21041435503.

It is not a weakly prime, because it can be changed into another prime (21041435131) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10520717765 + 10520717766.

It is an arithmetic number, because the mean of its divisors is an integer number (10520717766).

Almost surely, 2^21041435531 is an apocalyptic number.

21041435531 is a deficient number, since it is larger than the sum of its proper divisors (1).

21041435531 is an equidigital number, since it uses as much as digits as its factorization.

21041435531 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 7200, while the sum is 29.

Adding to 21041435531 its reverse (13553414012), we get a palindrome (34594849543).

The spelling of 21041435531 in words is "twenty-one billion, forty-one million, four hundred thirty-five thousand, five hundred thirty-one".