521027921 has 2 divisors, whose sum is σ = 521027922. Its totient is φ = 521027920.

The previous prime is 521027911. The next prime is 521027953. The reversal of 521027921 is 129720125.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 273406225 + 247621696 = 16535^2 + 15736^2 .

It is a cyclic number.

It is not a de Polignac number, because 521027921 - 2²² = 516833617 is a prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (521027911) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 260513960 + 260513961.

It is an arithmetic number, because the mean of its divisors is an integer number (260513961).

Almost surely, 2^521027921 is an apocalyptic number.

It is an amenable number.

521027921 is a deficient number, since it is larger than the sum of its proper divisors (1).

521027921 is an equidigital number, since it uses as much as digits as its factorization.

521027921 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 2520, while the sum is 29.

The square root of 521027921 is about 22826.0360334422. The cubic root of 521027921 is about 804.6746732698.

The spelling of 521027921 in words is "five hundred twenty-one million, twenty-seven thousand, nine hundred twenty-one".