21061696 has 14 divisors (see below), whose sum is σ = 41794430. Its totient is φ = 10530816.

The previous prime is 21061693. The next prime is 21061717. The reversal of 21061696 is 69616012.

It can be written as a sum of positive squares in only one way, i.e., 15492096 + 5569600 = 3936^2 + 2360^2 .

It is not an unprimeable number, because it can be changed into a prime (21061693) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 164481 + ... + 164608.

Almost surely, 2^21061696 is an apocalyptic number.

It is an amenable number.

21061696 is a deficient number, since it is larger than the sum of its proper divisors (20732734).

21061696 is an equidigital number, since it uses as much as digits as its factorization.

21061696 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 329101 (or 329091 counting only the distinct ones).

The product of its (nonzero) digits is 3888, while the sum is 31.

The square root of 21061696 is about 4589.3023434941. The cubic root of 21061696 is about 276.1623353621.

The spelling of 21061696 in words is "twenty-one million, sixty-one thousand, six hundred ninety-six".