21004710722 has 6 divisors (see below), whose sum is σ = 31507373529. Its totient is φ = 10502252880.

The previous prime is 21004710679. The next prime is 21004710751. The reversal of 21004710722 is 22701740012.

It can be written as a sum of positive squares in 2 ways, for example, as 11681070241 + 9323640481 = 108079^2 + 96559^2 .

It is an ABA number since it can be written as A⋅B^A, here for A=2, B=102481.

It is a super-2 number, since 2×21004710722² (a number of 21 digits) contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 21004710691 and 21004710700.

It is an unprimeable number.

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 2 ways as a sum of consecutive naturals, for example, 153722 + ... + 256202.

Almost surely, 2^21004710722 is an apocalyptic number.

21004710722 is a deficient number, since it is larger than the sum of its proper divisors (10502662807).

21004710722 is an frugal number, since it uses more digits than its factorization.

21004710722 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 204964 (or 102483 counting only the distinct ones).

The product of its (nonzero) digits is 1568, while the sum is 26.

Multiplying 21004710722 by its product of nonzero digits (1568), we get a square (32935386412096 = 5738936²).

The spelling of 21004710722 in words is "twenty-one billion, four million, seven hundred ten thousand, seven hundred twenty-two".