521401871 has 2 divisors, whose sum is σ = 521401872. Its totient is φ = 521401870.

The previous prime is 521401847. The next prime is 521401897. The reversal of 521401871 is 178104125.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 521401871 - 2⁶ = 521401807 is a prime.

It is a super-2 number, since 2×521401871² = 543719822164601282, which contains 22 as substring.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (521401801) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 260700935 + 260700936.

It is an arithmetic number, because the mean of its divisors is an integer number (260700936).

Almost surely, 2^521401871 is an apocalyptic number.

521401871 is a deficient number, since it is larger than the sum of its proper divisors (1).

521401871 is an equidigital number, since it uses as much as digits as its factorization.

521401871 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 2240, while the sum is 29.

The square root of 521401871 is about 22834.2258682006. The cubic root of 521401871 is about 804.8671364896.

Adding to 521401871 its reverse (178104125), we get a palindrome (699505996).

The spelling of 521401871 in words is "five hundred twenty-one million, four hundred one thousand, eight hundred seventy-one".