521106021 has 8 divisors (see below), whose sum is σ = 772008960. Its totient is φ = 347403996.

The previous prime is 521105987. The next prime is 521106073. The reversal of 521106021 is 120601125.

521106021 is a `hidden beast` number, since 52 + 1 + 10 + 602 + 1 = 666.

It is not a de Polignac number, because 521106021 - 2⁶ = 521105957 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 521105985 and 521106003.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (521106221) 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 7 ways as a sum of consecutive naturals, for example, 9650085 + ... + 9650138.

It is an arithmetic number, because the mean of its divisors is an integer number (96501120).

Almost surely, 2^521106021 is an apocalyptic number.

It is an amenable number.

521106021 is a deficient number, since it is larger than the sum of its proper divisors (250902939).

521106021 is a wasteful number, since it uses less digits than its factorization.

521106021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 19300232 (or 19300226 counting only the distinct ones).

The product of its (nonzero) digits is 120, while the sum is 18.

The square root of 521106021 is about 22827.7467350591. The cubic root of 521106021 is about 804.7148770987.

Adding to 521106021 its reverse (120601125), we get a palindrome (641707146).

The spelling of 521106021 in words is "five hundred twenty-one million, one hundred six thousand, twenty-one".