20725817 has 8 divisors (see below), whose sum is σ = 23721600. Its totient is φ = 17738784.

The previous prime is 20725813. The next prime is 20725853. The reversal of 20725817 is 71852702.

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

It is not a de Polignac number, because 20725817 - 2² = 20725813 is a prime.

It is not an unprimeable number, because it can be changed into a prime (20725813) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 4109 + ... + 7637.

It is an arithmetic number, because the mean of its divisors is an integer number (2965200).

Almost surely, 2^20725817 is an apocalyptic number.

It is an amenable number.

20725817 is a deficient number, since it is larger than the sum of its proper divisors (2995783).

20725817 is an equidigital number, since it uses as much as digits as its factorization.

20725817 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4375.

The product of its (nonzero) digits is 7840, while the sum is 32.

The square root of 20725817 is about 4552.5615866235. The cubic root of 20725817 is about 274.6864393017.

The spelling of 20725817 in words is "twenty million, seven hundred twenty-five thousand, eight hundred seventeen".