21208496737 has 8 divisors (see below), whose sum is σ = 21255724640. Its totient is φ = 21161295360.

The previous prime is 21208496723. The next prime is 21208496759. The reversal of 21208496737 is 73769480212.

It is a happy number.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 21208496737 - 2³¹ = 19061013089 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21208496797) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 3245089 + ... + 3251617.

It is an arithmetic number, because the mean of its divisors is an integer number (2656965580).

Almost surely, 2^21208496737 is an apocalyptic number.

It is an amenable number.

21208496737 is a deficient number, since it is larger than the sum of its proper divisors (47227903).

21208496737 is an equidigital number, since it uses as much as digits as its factorization.

21208496737 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 13263.

The product of its (nonzero) digits is 1016064, while the sum is 49.

The spelling of 21208496737 in words is "twenty-one billion, two hundred eight million, four hundred ninety-six thousand, seven hundred thirty-seven".