20725646 has 8 divisors (see below), whose sum is σ = 31552680. Its totient is φ = 10208088.

The previous prime is 20725631. The next prime is 20725667. The reversal of 20725646 is 64652702.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 77201 + ... + 77468.

It is an arithmetic number, because the mean of its divisors is an integer number (3944085).

Almost surely, 2^20725646 is an apocalyptic number.

20725646 is a deficient number, since it is larger than the sum of its proper divisors (10827034).

20725646 is a wasteful number, since it uses less digits than its factorization.

20725646 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 154738.

The product of its (nonzero) digits is 20160, while the sum is 32.

The square root of 20725646 is about 4552.5428059492. The cubic root of 20725646 is about 274.6856838589.

The spelling of 20725646 in words is "twenty million, seven hundred twenty-five thousand, six hundred forty-six".