521113823 has 4 divisors (see below), whose sum is σ = 521287128. Its totient is φ = 520940520.

The previous prime is 521113819. The next prime is 521113841. The reversal of 521113823 is 328311125.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 521113823 - 2² = 521113819 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 521113792 and 521113801.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (521115823) 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, 82061 + ... + 88182.

It is an arithmetic number, because the mean of its divisors is an integer number (130321782).

Almost surely, 2^521113823 is an apocalyptic number.

521113823 is a deficient number, since it is larger than the sum of its proper divisors (173305).

521113823 is a wasteful number, since it uses less digits than its factorization.

521113823 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 173304.

The product of its digits is 1440, while the sum is 26.

The square root of 521113823 is about 22827.9176229458. The cubic root of 521113823 is about 804.7188931427.

Adding to 521113823 its reverse (328311125), we get a palindrome (849424948).

The spelling of 521113823 in words is "five hundred twenty-one million, one hundred thirteen thousand, eight hundred twenty-three".