21034656 has 36 divisors (see below), whose sum is σ = 59818122. Its totient is φ = 7011456.

The previous prime is 21034613. The next prime is 21034667. The reversal of 21034656 is 65643012.

21034656 is a `hidden beast` number, since 2 + 1 + 0 + 3 + 4 + 656 = 666.

It can be written as a sum of positive squares in only one way, i.e., 12531600 + 8503056 = 3540^2 + 2916^2 .

It is a tau number, because it is divible by the number of its divisors (36).

It is an unprimeable number.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 36231 + ... + 36806.

Almost surely, 2^21034656 is an apocalyptic number.

It is an amenable number.

21034656 is an abundant number, since it is smaller than the sum of its proper divisors (38783466).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

21034656 is a wasteful number, since it uses less digits than its factorization.

21034656 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 73053 (or 73042 counting only the distinct ones).

The product of its (nonzero) digits is 4320, while the sum is 27.

The square root of 21034656 is about 4586.3554157959. The cubic root of 21034656 is about 276.0441013334.

Adding to 21034656 its reverse (65643012), we get a palindrome (86677668).

The spelling of 21034656 in words is "twenty-one million, thirty-four thousand, six hundred fifty-six".