521213541 has 4 divisors (see below), whose sum is σ = 694951392. Its totient is φ = 347475692.

The previous prime is 521213521. The next prime is 521213543. The reversal of 521213541 is 145312125.

It is a happy number.

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 521213541 - 2²³ = 512824933 is a prime.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (521213543) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 86868921 + ... + 86868926.

It is an arithmetic number, because the mean of its divisors is an integer number (173737848).

Almost surely, 2^521213541 is an apocalyptic number.

It is an amenable number.

521213541 is a deficient number, since it is larger than the sum of its proper divisors (173737851).

521213541 is a wasteful number, since it uses less digits than its factorization.

521213541 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 173737850.

The product of its digits is 1200, while the sum is 24.

The square root of 521213541 is about 22830.1016423493. The cubic root of 521213541 is about 804.7702189997.

Adding to 521213541 its reverse (145312125), we get a palindrome (666525666).

The spelling of 521213541 in words is "five hundred twenty-one million, two hundred thirteen thousand, five hundred forty-one".