20725471 has 4 divisors (see below), whose sum is σ = 22319752. Its totient is φ = 19131192.

The previous prime is 20725469. The next prime is 20725477. The reversal of 20725471 is 17452702.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 17452702 = 2 ⋅8726351.

It is a cyclic number.

It is not a de Polignac number, because 20725471 - 2¹ = 20725469 is a prime.

It is a super-3 number, since 3×20725471³ (a number of 23 digits) contains 333 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20725477) 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 3 ways as a sum of consecutive naturals, for example, 797121 + ... + 797146.

It is an arithmetic number, because the mean of its divisors is an integer number (5579938).

Almost surely, 2^20725471 is an apocalyptic number.

20725471 is a deficient number, since it is larger than the sum of its proper divisors (1594281).

20725471 is a wasteful number, since it uses less digits than its factorization.

20725471 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1594280.

The product of its (nonzero) digits is 3920, while the sum is 28.

The square root of 20725471 is about 4552.5235858807. The cubic root of 20725471 is about 274.6849107405.

The spelling of 20725471 in words is "twenty million, seven hundred twenty-five thousand, four hundred seventy-one".