20525111 has 4 divisors (see below), whose sum is σ = 21605400. Its totient is φ = 19444824.

The previous prime is 20525101. The next prime is 20525129. The reversal of 20525111 is 11152502.

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

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-20525111 is a prime.

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 20525111.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20525101) 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, 540116 + ... + 540153.

It is an arithmetic number, because the mean of its divisors is an integer number (5401350).

Almost surely, 2^20525111 is an apocalyptic number.

20525111 is a deficient number, since it is larger than the sum of its proper divisors (1080289).

20525111 is a wasteful number, since it uses less digits than its factorization.

20525111 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1080288.

The product of its (nonzero) digits is 100, while the sum is 17.

The square root of 20525111 is about 4530.4647664450. The cubic root of 20525111 is about 273.7968862513.

Adding to 20525111 its reverse (11152502), we get a palindrome (31677613).

The spelling of 20525111 in words is "twenty million, five hundred twenty-five thousand, one hundred eleven".