21035225531 has 2 divisors, whose sum is σ = 21035225532. Its totient is φ = 21035225530.

The previous prime is 21035225509. The next prime is 21035225567. The reversal of 21035225531 is 13552253012.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 21035225531 - 2⁶ = 21035225467 is a prime.

It is a super-2 number, since 2×21035225531² (a number of 21 digits) contains 22 as substring.

It is a Sophie Germain prime.

It is a junction number, because it is equal to n+sod(n) for n = 21035225494 and 21035225503.

It is not a weakly prime, because it can be changed into another prime (21035225581) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10517612765 + 10517612766.

It is an arithmetic number, because the mean of its divisors is an integer number (10517612766).

Almost surely, 2^21035225531 is an apocalyptic number.

21035225531 is a deficient number, since it is larger than the sum of its proper divisors (1).

21035225531 is an equidigital number, since it uses as much as digits as its factorization.

21035225531 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 9000, while the sum is 29.

Adding to 21035225531 its reverse (13552253012), we get a palindrome (34587478543).

The spelling of 21035225531 in words is "twenty-one billion, thirty-five million, two hundred twenty-five thousand, five hundred thirty-one".