20525471 has 4 divisors (see below), whose sum is σ = 20540472. Its totient is φ = 20510472.

The previous prime is 20525459. The next prime is 20525497. The reversal of 20525471 is 17452502.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 20525471 - 2¹⁰ = 20524447 is a prime.

It is a super-3 number, since 3×20525471³ (a number of 23 digits) contains 333 as substring.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 20525471.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20525411) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 5216 + ... + 8261.

It is an arithmetic number, because the mean of its divisors is an integer number (5135118).

Almost surely, 2^20525471 is an apocalyptic number.

20525471 is a deficient number, since it is larger than the sum of its proper divisors (15001).

20525471 is a wasteful number, since it uses less digits than its factorization.

20525471 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 15000.

The product of its (nonzero) digits is 2800, while the sum is 26.

The square root of 20525471 is about 4530.5044972939. The cubic root of 20525471 is about 273.7984869946.

Adding to 20525471 its reverse (17452502), we get a palindrome (37977973).

The spelling of 20525471 in words is "twenty million, five hundred twenty-five thousand, four hundred seventy-one".