521225407 has 2 divisors, whose sum is σ = 521225408. Its totient is φ = 521225406.

The previous prime is 521225387. The next prime is 521225459. The reversal of 521225407 is 704522125.

It is a weak prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-521225407 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (521223407) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 260612703 + 260612704.

It is an arithmetic number, because the mean of its divisors is an integer number (260612704).

Almost surely, 2^521225407 is an apocalyptic number.

521225407 is a deficient number, since it is larger than the sum of its proper divisors (1).

521225407 is an equidigital number, since it uses as much as digits as its factorization.

521225407 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 5600, while the sum is 28.

The square root of 521225407 is about 22830.3615170676. The cubic root of 521225407 is about 804.7763261133.

The spelling of 521225407 in words is "five hundred twenty-one million, two hundred twenty-five thousand, four hundred seven".