20725685 has 8 divisors (see below), whose sum is σ = 24935256. Its totient is φ = 16537600.

The previous prime is 20725673. The next prime is 20725693. The reversal of 20725685 is 58652702.

It can be written as a sum of positive squares in 4 ways, for example, as 2798929 + 17926756 = 1673^2 + 4234^2 .

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

It is not a de Polignac number, because 20725685 - 2²² = 16531381 is a prime.

It is a Duffinian number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 3164 + ... + 7173.

It is an arithmetic number, because the mean of its divisors is an integer number (3116907).

Almost surely, 2^20725685 is an apocalyptic number.

It is an amenable number.

20725685 is a deficient number, since it is larger than the sum of its proper divisors (4209571).

20725685 is a wasteful number, since it uses less digits than its factorization.

20725685 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10743.

The product of its (nonzero) digits is 33600, while the sum is 35.

The square root of 20725685 is about 4552.5470892677. The cubic root of 20725685 is about 274.6858561532.

The spelling of 20725685 in words is "twenty million, seven hundred twenty-five thousand, six hundred eighty-five".