21521113049 has 2 divisors, whose sum is σ = 21521113050. Its totient is φ = 21521113048.

The previous prime is 21521112941. The next prime is 21521113067. The reversal of 21521113049 is 94031112512.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 18441640000 + 3079473049 = 135800^2 + 55493^2 .

It is a cyclic number.

It is not a de Polignac number, because 21521113049 - 2¹² = 21521108953 is a prime.

It is a super-3 number, since 3×21521113049³ (a number of 32 digits) contains 333 as substring.

It is not a weakly prime, because it can be changed into another prime (21521113069) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10760556524 + 10760556525.

It is an arithmetic number, because the mean of its divisors is an integer number (10760556525).

Almost surely, 2^21521113049 is an apocalyptic number.

It is an amenable number.

21521113049 is a deficient number, since it is larger than the sum of its proper divisors (1).

21521113049 is an equidigital number, since it uses as much as digits as its factorization.

21521113049 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 2160, while the sum is 29.

The spelling of 21521113049 in words is "twenty-one billion, five hundred twenty-one million, one hundred thirteen thousand, forty-nine".