521521321401 has 6 divisors (see below), whose sum is σ = 753308575370. Its totient is φ = 347680880928.

The previous prime is 521521321393. The next prime is 521521321459. The reversal of 521521321401 is 104123125125.

It is a happy number.

521521321401 is a `hidden beast` number, since 5 + 21 + 5 + 213 + 21 + 401 = 666.

It can be written as a sum of positive squares in only one way, i.e., 309999514176 + 211521807225 = 556776^2 + 459915^2 .

It is not a de Polignac number, because 521521321401 - 2³ = 521521321393 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (521521321501) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 28973406736 + ... + 28973406753.

Almost surely, 2^521521321401 is an apocalyptic number.

It is an amenable number.

521521321401 is a deficient number, since it is larger than the sum of its proper divisors (231787253969).

521521321401 is a wasteful number, since it uses less digits than its factorization.

521521321401 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 57946813495 (or 57946813492 counting only the distinct ones).

The product of its (nonzero) digits is 2400, while the sum is 27.

Adding to 521521321401 its reverse (104123125125), we get a palindrome (625644446526).

The spelling of 521521321401 in words is "five hundred twenty-one billion, five hundred twenty-one million, three hundred twenty-one thousand, four hundred one".