20723647 has 8 divisors (see below), whose sum is σ = 23724576. Its totient is φ = 17732832.

The previous prime is 20723639. The next prime is 20723669. The reversal of 20723647 is 74632702.

It is a happy number.

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

It is a cyclic number.

It is not a de Polignac number, because 20723647 - 2³ = 20723639 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20723617) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 2553 + ... + 6925.

It is an arithmetic number, because the mean of its divisors is an integer number (2965572).

Almost surely, 2^20723647 is an apocalyptic number.

20723647 is a deficient number, since it is larger than the sum of its proper divisors (3000929).

20723647 is an equidigital number, since it uses as much as digits as its factorization.

20723647 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5057.

The product of its (nonzero) digits is 14112, while the sum is 31.

The square root of 20723647 is about 4552.3232530215. The cubic root of 20723647 is about 274.6768523796.

The spelling of 20723647 in words is "twenty million, seven hundred twenty-three thousand, six hundred forty-seven".