21071949415 has 16 divisors (see below), whose sum is σ = 28052645760. Its totient is φ = 15065305120.

The previous prime is 21071949401. The next prime is 21071949427. The reversal of 21071949415 is 51494917012.

It is not a de Polignac number, because 21071949415 - 2⁷ = 21071949287 is a prime.

It is a congruent number.

It is an unprimeable number.

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 in 15 ways as a sum of consecutive naturals, for example, 3243589 + ... + 3250078.

It is an arithmetic number, because the mean of its divisors is an integer number (1753290360).

Almost surely, 2^21071949415 is an apocalyptic number.

21071949415 is a deficient number, since it is larger than the sum of its proper divisors (6980696345).

21071949415 is a wasteful number, since it uses less digits than its factorization.

21071949415 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6493742.

The product of its (nonzero) digits is 90720, while the sum is 43.

The spelling of 21071949415 in words is "twenty-one billion, seventy-one million, nine hundred forty-nine thousand, four hundred fifteen".