21073030949 has 4 divisors (see below), whose sum is σ = 21642572364. Its totient is φ = 20503489536.

The previous prime is 21073030943. The next prime is 21073030973. The reversal of 21073030949 is 94903037012.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 19672026049 + 1401004900 = 140257^2 + 37430^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21073030949 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21073030943) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 284770652 + ... + 284770725.

It is an arithmetic number, because the mean of its divisors is an integer number (5410643091).

Almost surely, 2^21073030949 is an apocalyptic number.

It is an amenable number.

21073030949 is a deficient number, since it is larger than the sum of its proper divisors (569541415).

21073030949 is an equidigital number, since it uses as much as digits as its factorization.

21073030949 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 569541414.

The product of its (nonzero) digits is 40824, while the sum is 38.

The spelling of 21073030949 in words is "twenty-one billion, seventy-three million, thirty thousand, nine hundred forty-nine".