20521061 has 4 divisors (see below), whose sum is σ = 22386624. Its totient is φ = 18655500.

The previous prime is 20521049. The next prime is 20521063. The reversal of 20521061 is 16012502.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 20521061 - 2¹⁴ = 20504677 is a prime.

It is a super-2 number, since 2×20521061² = 842227889131442, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20521063) 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, 932765 + ... + 932786.

It is an arithmetic number, because the mean of its divisors is an integer number (5596656).

Almost surely, 2^20521061 is an apocalyptic number.

It is an amenable number.

20521061 is a deficient number, since it is larger than the sum of its proper divisors (1865563).

20521061 is a wasteful number, since it uses less digits than its factorization.

20521061 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1865562.

The product of its (nonzero) digits is 120, while the sum is 17.

The square root of 20521061 is about 4530.0177703846. The cubic root of 20521061 is about 273.7788765991.

Adding to 20521061 its reverse (16012502), we get a palindrome (36533563).

It can be divided in two parts, 2052 and 1061, that added together give a palindrome (3113).

The spelling of 20521061 in words is "twenty million, five hundred twenty-one thousand, sixty-one".