21698468416 has 21 divisors (see below), whose sum is σ = 43060236841. Its totient is φ = 10848644992.

The previous prime is 21698468377. The next prime is 21698468419. The reversal of 21698468416 is 61486489612.

The square root of 21698468416 is 147304.

It is a perfect power (a square), and thus also a powerful number.

It can be written as a sum of positive squares in only one way, i.e., 5697230400 + 16001238016 = 75480^2 + 126496^2 .

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21698468419) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 2 ways as a sum of consecutive naturals, for example, 1169226 + ... + 1187638.

Almost surely, 2^21698468416 is an apocalyptic number.

21698468416 is the 147304-th square number.

It is an amenable number.

21698468416 is a deficient number, since it is larger than the sum of its proper divisors (21361768425).

21698468416 is an frugal number, since it uses more digits than its factorization.

21698468416 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 36838 (or 18415 counting only the distinct ones).

The product of its digits is 3981312, while the sum is 55.

The spelling of 21698468416 in words is "twenty-one billion, six hundred ninety-eight million, four hundred sixty-eight thousand, four hundred sixteen".