521871401 has 4 divisors (see below), whose sum is σ = 524603904. Its totient is φ = 519138900.

The previous prime is 521871397. The next prime is 521871433. The reversal of 521871401 is 104178125.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 521871401 - 2² = 521871397 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (521871451) 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 in 3 ways as a sum of consecutive naturals, for example, 1365965 + ... + 1366346.

It is an arithmetic number, because the mean of its divisors is an integer number (131150976).

Almost surely, 2^521871401 is an apocalyptic number.

It is an amenable number.

521871401 is a deficient number, since it is larger than the sum of its proper divisors (2732503).

521871401 is a wasteful number, since it uses less digits than its factorization.

521871401 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2732502.

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

The square root of 521871401 is about 22844.5048315782. The cubic root of 521871401 is about 805.1086622088.

The spelling of 521871401 in words is "five hundred twenty-one million, eight hundred seventy-one thousand, four hundred one".