407243521 has 2 divisors, whose sum is σ = 407243522. Its totient is φ = 407243520.

The previous prime is 407243519. The next prime is 407243537. The reversal of 407243521 is 125342704.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 359481600 + 47761921 = 18960^2 + 6911^2 .

It is a cyclic number.

It is not a de Polignac number, because 407243521 - 2¹ = 407243519 is a prime.

Together with 407243519, it forms a pair of twin primes.

It is a self number, because there is not a number n which added to its sum of digits gives 407243521.

It is not a weakly prime, because it can be changed into another prime (407243581) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 203621760 + 203621761.

It is an arithmetic number, because the mean of its divisors is an integer number (203621761).

Almost surely, 2^407243521 is an apocalyptic number.

It is an amenable number.

407243521 is a deficient number, since it is larger than the sum of its proper divisors (1).

407243521 is an equidigital number, since it uses as much as digits as its factorization.

407243521 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 6720, while the sum is 28.

The square root of 407243521 is about 20180.2755432130. The cubic root of 407243521 is about 741.2272798589.

The spelling of 407243521 in words is "four hundred seven million, two hundred forty-three thousand, five hundred twenty-one".