521540120 has 64 divisors (see below), whose sum is σ = 1264032000. Its totient is φ = 193027968.

The previous prime is 521540119. The next prime is 521540141. The reversal of 521540120 is 21045125.

It is a super-2 number, since 2×521540120² = 544008193539228800, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (20).

It is a junction number, because it is equal to n+sod(n) for n = 521540092 and 521540101.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 24701 + ... + 40659.

It is an arithmetic number, because the mean of its divisors is an integer number (19750500).

Almost surely, 2^521540120 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 521540120, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (632016000).

521540120 is an abundant number, since it is smaller than the sum of its proper divisors (742491880).

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

521540120 is a wasteful number, since it uses less digits than its factorization.

521540120 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 16032 (or 16028 counting only the distinct ones).

The product of its (nonzero) digits is 400, while the sum is 20.

The square root of 521540120 is about 22837.2528995937. The cubic root of 521540120 is about 804.9382666804.

Adding to 521540120 its reverse (21045125), we get a palindrome (542585245).

The spelling of 521540120 in words is "five hundred twenty-one million, five hundred forty thousand, one hundred twenty".