521411665140 has 288 divisors, whose sum is σ = 1698177761280. Its totient is φ = 129030340608.

The previous prime is 521411665109. The next prime is 521411665141. The reversal of 521411665140 is 41566114125.

521411665140 is a `hidden beast` number, since 5 + 21 + 4 + 116 + 6 + 514 + 0 = 666.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a junction number, because it is equal to n+sod(n) for n = 521411665095 and 521411665104.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (521411665141) by changing a digit.

It is a polite number, since it can be written in 95 ways as a sum of consecutive naturals, for example, 313535949 + ... + 313537611.

It is an arithmetic number, because the mean of its divisors is an integer number (5896450560).

Almost surely, 2^521411665140 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 521411665140, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (849088880640).

521411665140 is an abundant number, since it is smaller than the sum of its proper divisors (1176766096140).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

521411665140 is a wasteful number, since it uses less digits than its factorization.

521411665140 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3071 (or 3066 counting only the distinct ones).

The product of its (nonzero) digits is 28800, while the sum is 36.

Adding to 521411665140 its reverse (41566114125), we get a palindrome (562977779265).

The spelling of 521411665140 in words is "five hundred twenty-one billion, four hundred eleven million, six hundred sixty-five thousand, one hundred forty".