21078652 has 12 divisors (see below), whose sum is σ = 42157360. Its totient is φ = 9033696.

The previous prime is 21078637. The next prime is 21078703. The reversal of 21078652 is 25687012.

21078652 is an admirable number.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 376377 + ... + 376432.

Almost surely, 2^21078652 is an apocalyptic number.

It is an amenable number.

21078652 is a primitive abundant number, since it is smaller than the sum of its proper divisors, none of which is abundant.

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

21078652 is a wasteful number, since it uses less digits than its factorization.

21078652 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 752820 (or 752818 counting only the distinct ones).

The product of its (nonzero) digits is 6720, while the sum is 31.

The square root of 21078652 is about 4591.1493114470. The cubic root of 21078652 is about 276.2364248770.

The spelling of 21078652 in words is "twenty-one million, seventy-eight thousand, six hundred fifty-two".