21149056507 has 2 divisors, whose sum is σ = 21149056508. Its totient is φ = 21149056506.

The previous prime is 21149056501. The next prime is 21149056543. The reversal of 21149056507 is 70565094112.

It is a weak prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21149056507 is a prime.

It is a super-2 number, since 2×21149056507² (a number of 21 digits) contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 21149056507.

It is not a weakly prime, because it can be changed into another prime (21149056501) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10574528253 + 10574528254.

It is an arithmetic number, because the mean of its divisors is an integer number (10574528254).

Almost surely, 2^21149056507 is an apocalyptic number.

21149056507 is a deficient number, since it is larger than the sum of its proper divisors (1).

21149056507 is an equidigital number, since it uses as much as digits as its factorization.

21149056507 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 75600, while the sum is 40.

The spelling of 21149056507 in words is "twenty-one billion, one hundred forty-nine million, fifty-six thousand, five hundred seven".